Epistolae Duae De Ratione Paschae

The Two Letters of Dionysius Exiguus on the Reckoning of Easter. First Letter Written in the Year of Christ 525, under the Consul Probus, Indiction 5. To the most blessed and most greatly desired lord, Bishop Petronius, Dionysius Exiguus. The reckoning of the Paschal feast, which the persistent demand of many has long and frequently required of us, we have now taken care to set forth in response to your prayers, following in all things the absolute and true judgment of the venerable three hundred and eighteen pontiffs who assembled at the city of Nicaea in Bithynia against the madness of Arius, even on this matter: they fixed the fourteenth moons of the Paschal observance by means of the cycle of nineteen years always returning into itself, stable and immovable, which in all ages glide through the same beginnings at which they recur, without any variation in their course. Moreover, they established this rule of the aforementioned cycle not so much by singular skill as by the illumination of the Holy Spirit, and they are seen to have set it as a firm and stable anchor for this reckoning of lunar measure; which rule, afterwards, some, either despising it out of arrogance or transgressing it out of ignorance, led astray by Jewish fables, handed down a different and contrary form of the unique feast.

And because no structure can stand without a solid foundation, in certain years they have preferred to set the Lord's Easter and the computation of the moon far differently, arranging disordered cycles: which not only lack any stability of recurrence, but also exhibit a course notable for error. But the blessed Athanasius, archbishop of the city of Alexandria, who himself was then a deacon of the pontiff Saint Alexander at the Council of Nicaea and was present as an assistant in all matters, and afterwards the venerable Theophilus and Cyril, never departed from this venerable constitution of the synod. Rather, diligently retaining that same nineteen-year cycle, which is called by the Greek term Enneacaidecaeteris, they are shown to have interpolated no variations into the paschal course. Finally, Pope Theophilus, dedicating a cycle of one hundred years to the elder Emperor Theodosius, and Saint Cyril, composing a cycle of ninety-five years, preserved this tradition of the holy council in all respects for observing the paschal fourteenth moons. And because for those who are studious and who seek to know what is true, the rule of that same cycle ought to adhere more firmly, we have believed it should be appended after our preface.

We have striven to complete this cycle of ninety-five years with all the diligence we could muster, setting forth the last of the blessed Cyril’s cycles—that is, his fifth cycle—in this work of ours, since six years of it still remained; and we declare that we have arranged the other five according to the norm of that same pontiff, or rather of the oft-mentioned Council of Nicaea. But because the holy Cyril began his first cycle in the one hundred and fifty-third year of Diocletian and ended his last in the two hundred and forty-seventh, we, beginning in the two hundred and forty-eighth year of that same tyrant rather than prince, have been unwilling to bind the memory of an impious persecutor to our cycles; instead we have chosen to mark the times of the years from the Incarnation of our Lord Jesus Christ, so that the beginning of our hope might be more familiar to us, and the cause of our redemption—that is, the passion of our Redeemer—might shine forth more clearly.

Moreover, we thought it necessary to warn the reader that this cycle of ninety-five years which we have made, when it begins to return to itself after the completion of its time, does not maintain the proposed stability in all respects. For although the years of our Lord Jesus Christ preserve their order in an unbroken series, and the indictions run through fifteen years in their usual revolution, and the epacts—which the Greeks call by that name, that is, the annual lunar additions of eleven days, which return into themselves at the end of thirty days—you will find noted down by fixed rules, and also the nineteen-year cycle and the paschal fourteenth moons you will find the same throughout the revolutions of all ages, yet the concurrent days of the weeks and the days of the Lord's Passover, and the moon of that Lord's day, cannot maintain a similar constancy. The reckoning of the concurrents of the weeks (or, of the seven days), which arises from the course of the sun, is completed in a perpetual cycle of seven years. In this, for each single year you will count one; only in that year in which there is a bissextile day will you add two; which cause also makes it appear that this cycle of ninety-five years does not agree with its recurrence in all respects. For while it does not differ in the other years, in those alone in which the bissextile day intervenes, the Lord's Passover with its moon occurs in a varying manner of reckoning. But those things which run through the times in a fixed order, by their stable circuit, can direct the variable cases without any difficulty.

And therefore, after the completion of the ninety-five years, when one who is diligent in these matters wishes to return to the beginning, let him not run back to the fifth cycle of Saint Cyril, which we have necessarily set before us, but let him run carefully to our first; and, in the order we have stated, through those cycles which maintain a fixed course, let him sustain the progress of those which seem to waver. We have also thought that this should be noted with no less care, lest we be deceived in the recognition of the first month. For from this almost the entire error of the Paschal discrepancy arises, when the beginning of the time is unknown. For when the almighty Lord commanded this most sacred solemnity to be celebrated by the children of Israel, who were being freed from Egyptian servitude, he says in the book of Exodus to Moses and Aaron in the land of Egypt: "This month shall be the beginning of months; it shall be the first of the months of the year" (Exod. 12:2). And likewise in the same place: "In the first month," he says, "on the fourteenth day of the month at evening you shall eat unleavened bread, until the twenty-first day of the same at evening" (Ibid., 18). Also in Deuteronomy, the same lawgiver Moses thus admonishes the people concerning this matter, saying: "Observe the month of new grain, and the first of the spring season, that you may keep the Passover to the Lord your God, because in that month the Lord your God led you out of Egypt by night" (Deut. 16:1 and following). By such divine authority it has been made clear that the Paschal festival ought to be celebrated in the first month, on the fourteenth day at evening, until the twenty-first.

But since the beginning of this month, or where it ends, is not clearly read there, the aforementioned three hundred and eighteen pontiffs, investigating more diligently the observance of the ancient custom, and that handed down from Saint Moses, as is related in the seventh book of the Ecclesiastical History, declared that the new moon which makes the beginning of the first month occurs from the eighth day before the Ides of March up to the day of the Nones of April; and that the fourteenth moon is to be sought diligently from the twelfth day before the Kalends of April up to the fourteenth day before the Kalends of May. And because this moon does not revolve equally with the course of the sun, it follows the occurrence of the vernal equinox within the space of so many days: which equinox is especially noted on the twelfth day before the Kalends of April, according to the opinions of all the Easterners, and especially of the Egyptians, who are more skilled than all others in calculation. In this matter, also, if the fourteenth moon should fall on a Sabbath (which is manifestly known to happen once in ninety-five years), then on the following Lord's day, that is, the eleventh day before the Kalends of April, with the fifteenth moon, the same holy synod without ambiguity established that Easter should be celebrated. It admonishes in every way that no one should seek the fourteenth moon of the paschal feast before the twelfth day before the Kalends of April; for it would be certain to be not of the first month, but of the last.

But we thought this also should not be passed over, that those who, estimating that the moon completes the course of its cycle in a space of thirty days, count twelve lunar months as three hundred and sixty days, and to these they also add five days, which antiquity called intercalary, so that they seem to fill out the solar year, are greatly in error. For a diligent investigation of the truth has shown that in two lunar cycles not sixty days, but fifty-nine, ought to be counted. And thus in twelve lunar months a total of three hundred and fifty-four days is collected; to which the Egyptians add the annual epacts, that is, eleven days, so that the lunar measure is finally made equal to the solar reckoning. That this is most true and most certain is confirmed by the judgment of the above-mentioned Fathers, who, according to this calculation of the Egyptians, handed down the fourteenth moons of the paschal observance. But some, ignorant of such great subtlety, or rather of such great sanction, while they seek other arguments of computation, depart from the path of truth. Whence it often happens that when the often-mentioned Fathers place the fourteenth moon, these suspect it to be the fifteenth; and what is the twenty-first, they pronounce to be the twenty-second. But for us, for whom love and care of the Christian religion exist, we ought by no means to depart from reason; but it is fitting to preserve with the most sincere observance the paschal rule fixed by them.

But how much we rely on the authority of these Fathers, who are spread throughout the whole world in the Churches, it is not laborious to show: since the Council at Nicaea, convened not long after their time, first decreed that their definition, which they had set forth concerning the Paschal reckoning, was in no way to be violated. Finally, in the sacred canons, under the seventy-ninth title, which is the first of the Antiochene Council itself, it is found expressed in these words: We decree that all who have dared to dissolve the definition of the holy and great Council which was assembled at Nicaea, in the presence of the most pious and venerable Emperor Constantine, concerning the salutary Paschal solemnity, are to be excommunicated and expelled from the Church; if, however, they persist in being contentious against those things which have been well decreed. And these things have been said concerning the laity. But if any of those who preside over the Church, whether bishop, or presbyter, or deacon, after this definition, should attempt, to the subversion of the people and the disturbance of the Churches, to assemble separately and to celebrate Pascha with the Jews; the holy synod has declared such a one already alien from the Church, because he has been a cause of corruption and disturbance not only to himself but to very many. And not only does it remove him from the ministry, but also those who after such condemnation attempt to communicate with him are to be condemned, and are also deprived of all external honor, which the holy rule and the priesthood of God have merited.

Not dissimilar to these are the pronouncements of the venerable Pope Leo, president of the apostolic see, who says: "Against the statutes of the canonical fathers, which many years of a very long age ago in the city of Nicaea were established by spiritual decrees, nothing is permitted to anyone to dare: so that if anyone should wish to decree something different, he would rather diminish himself than corrupt those statutes." And again: "In all ecclesiastical matters," he says, "we obey those laws which the Holy Spirit instituted through the three hundred and eighteen bishops for the peaceful observance of all priests: so that even if many more should decree something other than what they established, whatever is different from the aforesaid constitution is to be held in no reverence." Sufficiently, as we think, it is indicated to all, lest henceforth the most sacred Easter be celebrated otherwise than as established by the holy Fathers. But if perhaps someone with an obstinate mind should despise the testimonies of such great priests, he will also find similar matters briefly indicated in ecclesiastical history; and he will learn these same things made known by the report of many pontiffs, and especially of the blessed Athanasius, whom we mentioned above.

The same thing is attested by the letter of the holy Proterius, bishop of the city of Alexandria, to the same Pope Leo on this same paschal question; which letter, translating from Greek some years ago, we have seen fit to be appended to this work; and we have also subjoined the arguments sought out by the sagacity of the Egyptians, by which, if they should perhaps be unknown, the paschal titles can easily be found: that is, what year it is from the Incarnation of the Lord, and what the indiction is; also what the lunar cycle is, or the nineteen-year cycle; and the rest of similar things are sought by a compendium of calculation. May divine grace deign to preserve your blessedness praying for us. LETTER II. WRITTEN IN THE COMMON YEAR OF CHRIST 526. To my most highly reverend lords Boniface, chief notary, and Bonus, second notary, Dionysius Exiguus sends greetings. The rule of paschal observance, long urged by the holy and venerable bishop Petronius, I, compelled at last to commit to writing, had believed that thereafter all attack of diversity would be removed; especially since I had taken care to inculcate with all my might the authority of the three hundred and eighteen holy bishops who had assembled at Nicaea: who in that venerable council, fixing the nineteen-year cycle regularly, noted the fourteenth moons of paschal observance as immovable through all times according to the law of its revolution.

But since your Holiness, when the question of this matter arose, has now brought forth from the archive of the Roman Church the writings of the venerable bishop Paschasinus, who is known to have presided at the holy Council of Chalcedon in the person of the most blessed Pope Leo, writings directed to the same pope at that same time—writings which agree with evident reasoning with the holy Fathers—we have inserted them into this present work, so that we might also rely on the testimony of this man, who by a manifest miracle confirms the paschal decrees of the venerable pontiffs. As for the fact that in those same writings mention is made of common years and embolismic years, and that this reckoning, which is said to descend from the tradition of the Hebrews, is greatly sought after by some who wish to know whether it seems to accord with the ancestral rule, we have deemed it necessary to set forth this knowledge as well, lest it be found to disagree in any respect, and to do so with compressed brevity. Let us know, therefore, that the same nineteen-year cycle always revolves within itself through an ogdoad and a hendecad. For the number itself is unfolded by eight and eleven. The ogdoad, then, which begins from the first nineteen-year cycle, which is the seventeenth lunar [cycle], is completed in such a way that it has the first and second years as common, that is, smaller; the third as embolismic, that is, larger; the fourth and fifth years likewise common; the sixth as embolismic; the seventh as common; the eighth as embolismic. And by this means, five common years and three embolismic years are constantly assigned to the ogdoad.

A common year, however, collects twelve lunar months, which make three hundred fifty-four days. An embolismic year, on the other hand, is shown to have both thirteen moons and three hundred eighty-four days. Likewise, the hendecas runs according to this rule. It begins in the ninth year of the nineteen-year cycle, which is the sixth lunar year: its first and second years are common, the third embolismic; the fourth and fifth common, the sixth embolismic; the seventh and eighth common; the ninth embolismic; the tenth common, the eleventh embolismic: and thus the hendecas is completed with seven common years and four embolismic years. The rationale for the embolismic years is shown to exist because they seem to make up for the deficiencies of the common years, so that the lunar course may be equalized to the solar time. For although the moon goes around the circle of the solar year through each month, it is not able to fulfill its perfection in its own twelve months. Indeed, in common years, eleven days are seen to be lacking for the moon to match the reckoning of the solar year. In embolismic years, however, the moon appears to exceed that same solar year by nineteen days. Therefore, let us bring forth the years of the ogdoad and the hendecas according to the order of the aforementioned cycle; and we will clearly prove that, over eight years and eleven, the moon's course contends with the sun: when it gathers as many days as the sun has run.

In the ogdoad we said that five years are common, three embolismic. Therefore five times three hundred fifty-four make one thousand seven hundred seventy; and three times three hundred eighty-four make one thousand one hundred fifty-two, and thus together they make two thousand nine hundred twenty-two. Similarly, eight solar years, if reduced to a sum, that is eight times three hundred sixty-five and a quarter, together make two thousand nine hundred twenty-two. In like manner, the years of the hendecad, which are seven common and four embolismic, if you gather them into a sum by the calculation we have described, you will find almost the same amount as eleven solar years produce; that is, four thousand fourteen. This, therefore, is the principle of embolisms, as we have said before, that by their increments they compensate for the deficiencies of common years. But now I will show you the most beautiful and illustrious collection of the nineteen-year cycle itself, through which you may thereafter remove all ambiguity, if any should arise; nor should anyone be so struck by excessive stupor that he does not rejoice in the light of truth shown to him, and, having abandoned the darkness of ignorance, does not immediately acquiesce to such great reasoning. From the fifteenth moon of the paschal feast of the preceding year, for example, to the fourteenth of the following year, which we seek, if it is a common year, it will have three hundred fifty-four days; if an embolismic year, three hundred eighty-four.

But if one day more or less should occur, the error is evident. Except, of course, for the first year of the oft-mentioned nineteen-year cycle, which we take care to count from the fourteenth moon of the last Passover, that is, of the nineteenth year, up to the fourteenth moon of that same first year. For this reason, that same last year, then retaining eighteen epacts, that is, lunar additions, supplies to the first year not eleven days, as is customary in the other years, but twelve. And because the cycles are completed at the end of thirty days, no epact is placed at the beginning of the cycle itself; but the second year receives eleven epacts: and therefore, as we have said, from the fifteenth moon of the Passover of the first cycle up to its end, in the common and embolismic years, we find the prescribed days, there is no doubt. But if otherwise the inexperience of calculators has perhaps at some time set it forth, by this observance the falsity of their reckoning will be proven.

And so that this may be understood more clearly, let us demonstrate with the example of the present year. For the indiction is the fourth, and the lunar cycle the eleventh; the nineteen-year cycle the fourteenth. And since it is the sixth year of the bendecad, it must necessarily be an embolismic year. Therefore, let us carefully inquire how many days there are from the fifteenth moon of the past feast to the fourteenth of the present; and we will undoubtedly find when we ought to celebrate Easter. In the past year, during the third indiction, who would doubt that the fourteenth moon of Easter occurred on the ninth day before the Kalends of April, that is, the twenty-fourth day of the month of March, if he is known to have even the slightest care for this matter? And therefore, let us begin our count from the eighth day before the Kalends of April; we have seven days of March, thirty of April, thirty-one of May, thirty of June, thirty-one of July, thirty-one of August, thirty of September, thirty-one of October, thirty of November, thirty-one of December, thirty-one of January, twenty-eight of February, thirty-one of March, and twelve days of April, which is the day before the Ides of April. Together they make three hundred eighty-four. But if, according to the definition of those who compute the moon otherwise than the truth holds, the fourteenth should occur not on the day before the Ides of April, but on the third day before the Ides, we would gather three hundred eighty-three days, with the number diminished; which is in no way allowed.

And so, whenever such a doubt arises, let us carefully count the days from the fifteenth moon of the past feast up to the fourteenth moon of the Pascha which we seek. And if it is a common year, we will find three hundred fifty-four days; if it is an embolismic year, we will find three hundred eighty-four: and no inequality will occur at all, because the rule of this cycle stands by this reasoning, whose clear formula we will set forth in the appended description. In the first year of the nineteen-year cycle, the lunar cycle being the seventeenth, from the fifteenth day before the Kalends of May to the Nones of April, because it is a common year, there are three hundred fifty-four days. In the second year of the nineteen-year cycle, the lunar cycle being the eighteenth, from the eighth day before the Ides of April to the eighth day before the Kalends of April, because it is a common year, there are three hundred fifty-four days. In the third year of the nineteen-year cycle, the lunar cycle being the nineteenth, from the seventh day before the Kalends of April to the Ides of April, because it is an embolismic year, there are three hundred eighty-four days.

In the fourth year of the decemnovennial cycle, the first lunar year, from the eighteenth day before the Kalends of May to the fourth day before the Nones of April, because it is a common year, there are three hundred fifty-four days. In the fifth year of the decemnovennial cycle, the second lunar year, from the third day before the Nones of April to the eleventh day before the Kalends of April, because it is a common year, there are three hundred fifty-four days. In the sixth year of the decemnovennial cycle, the third lunar year, from the tenth day before the Kalends of April to the fourth day before the Ides of April, because it is an embolismic year, there are three hundred eighty-four days. In the seventh year of the decemnovennial cycle, the fourth lunar year, from the third day before the Ides of April to the third day before the Kalends of April, because it is a common year, there are three hundred fifty-four days. In the eighth year of the decemnovennial cycle, the fifth lunar year, from the day before the Kalends of April to the fourteenth day before the Kalends of May, because it is an embolismic year, there are three hundred eighty-four days. In the ninth year of the decemnovennial cycle, the sixth lunar year, from the thirteenth day before the Kalends of May to the seventh day before the Ides of April, because it is a common year, there are three hundred fifty-four days.

In the tenth year of the decemnovennial cycle, the seventh lunar year, from the sixth day before the Ides of April to the sixth day before the Kalends of April, because it is a common year, there are three hundred fifty-four days. In the eleventh year of the decemnovennial cycle, the eighth lunar year, from the fifth day before the Kalends of April to the seventeenth day before the Kalends of May, because it is an embolismic year, there are three hundred eighty-four days. In the twelfth year of the decemnovennial cycle, the ninth lunar year, from the sixteenth day before the Kalends of May to the day before the Nones of April, because it is a common year, there are three hundred fifty-four days. In the thirteenth year of the decemnovennial cycle, the tenth lunar year, from the Nones of April to the ninth day before the Kalends of April, because it is a common year, there are three hundred fifty-four days. In the fourteenth year of the decemnovennial cycle, the eleventh lunar year, from the eighth day before the Kalends of April to the second day before the Ides of April, because it is an embolismic year, there are three hundred eighty-four days. In the fifteenth year of the decemnovennial cycle, the twelfth lunar year, from the Ides of April to the Kalends of April, because it is a common year, there are three hundred fifty-four days.

In the tenth year of the decemnovennial cycle, the sixteenth lunar year, from the fourth day before the Nones of April to the twelfth day before the Kalends of April, because it is a common year, there are three hundred fifty-four days. In the seventeenth year of the decemnovennial cycle, the fourteenth lunar year, from the eleventh day before the Kalends of April to the fifth day before the Ides of April, because it is an embolismic year, there are three hundred eighty-four days. In the eighteenth year of the decemnovennial cycle, the fifteenth lunar year, from the fourth day before the Ides of April to the fourth day before the Kalends of April, because it is a common year, there are three hundred fifty-four days. In the nineteenth year of the decemnovennial cycle, the sixteenth lunar year, from the third day before the Kalends of April to the fifteenth day before the Kalends of May, because it is an embolismic year, there are three hundred eighty-four days.