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Severus Sebokht, On the Constellations.  Revue de l'Orient Chretien (1929) pp.327-338. Introduction by François Nau

The treatise on the constellations, written in 660 by Severus Sebokht, Bishop of Kinnesrin.


Severus Sebokht has been known above all as a populariser among the Syrians of Greek philosophy.  (cf. E. Renan, De philosophia peripatetica apud Syros) We now know, thanks to a manuscript brought to light by Addai Scher and analysed in ROC 15 (1910), pp. 225-254, that he also played an important role in the transmission of Greek science.  This manuscript, (Paris Syr. 346 dated to 1309) only contains his correspondance, through the last years of his life with a certain Basil, priest and visitor in the island of Cyprus.  From which we can thus conclude that if he wrote 27 chapters in a few years to a single correspondant, his scientific activity must have been considerable.  

The first 18 chapters (folios 78-121v) form a separate treatise, which has its incipit and desinit, and to which Severus refers in a later work.  It is this treatise, devoted above all to the constellations, that we are translating here.  The first 5 chapters are directed against astrologers.  These attributing to the constellations effects related to their name, Severus shows at length that these names have been given arbitrarily and are thus, as he says, pure conventions, which have no relation with the nature of the stars.  We will give the text of chapter 4 because it contains long citations of Aratus which are missing most of the time in the Phenomena of that author, which is preserved in Greek.  |328 We will also give the text of chapter 5 because it contains all the astrological vocabulary already used by Bardesanes in the Book of the Laws of the Countries as well as the text containing the names of the constellations and of the principal stars, because these names are used constantly throughout the treatise.

Severus then leaves the astrologers to turn to cosmography, which must have been very fashionable because it was the basis for astrology:  the number of constellations, their names, remarkable stars.  The simultaneous rising and setting of the zodiac, and of other constellations.  Noteworthy circles of the celestial sphere; their position, constellations that they intersect.  For him (ch. 11) as likewise for Manilius (Astronomics, book 1, ch. 6.1ff), the milky way is a great circle.  The positions of these circles relative to the various climates leads him to give the names of the climates according to Ptolemy, the length of their days, their latitude.  He finishes with the extent of the inhabited and uninhabited earth and throws into relief the existence of the antipodes.  He also announces "the measure of the sky" but gives nothing which corresponds really to this title.

Two short fragments of chapters 17 and 18 have been edited without a translation by E. Sachau, after a manuscript of the British Museum, Add. 14538, of the 10th century, in Inedita Syriaca, Vienna 1870, pp. 127-134.  The rest is unpublished.

In the various manuscripts (Paris, British Museum, Cambridge, Berlin, Notre Dame des Semences) which preserve for us fragments of the works of Severus, this author is named ܢܨܝܒܢܝܐ, of Nisibis, or Nisibite, abbot and bishop of Kinnesrin.  He was thus from Nisibis.  Despite his surname Sebokht, which is Persian, he proclaims himself a Syrian.1 He must have been the superior of the monastery (abbot) then bishop of Kinnesrin, without doubt Chalcis, to the south of Aleppo.  As A. Baumstark has already remarked very well, Severus was never "Bishop of Nisibis" |329 cf. Geschichte der syr. Literatur, Bonn, 1922, p.246-7.2

In June 638 he wrote on the works of Aristotle 3; in 659 he assisted the Jacobite patriarch Theodore in a discussion with the Maronites before Al-Muawiah cf. ROC IV 1899 p.323; before 661 he wrote the treatise on the astrolabe which we have edited and translated (Paris 1899), because he refers to it twice in the treatise on the constellations written in 661 which we translate today; in 662 he wrote a letter on the epoch of the birth of Christ; a chapter on the climates (ms. 346, f. 134), is without doubt from this epoch because we find a reference in it to the treatise on the constellations written in 661.  Finally a treatise on the day when Easter should be celebrated in the year 665 which is perhaps by him leads us to hope that Severus was still alive in that year.  A. Baumstark (loc. cit.) places his death in 666-7. 

The sources used by Severus

References to Theon, Aratus and above all to Ptolemy are found in his works.  Severus Sebokht knew most of the works of Ptolemy: the Geography, the Mathematical Composition (Almagest), the Manual tables, and the works of astrology: the quadripartitum and its summary the Book of fruit.  He tells us this in the following text.  Ms. Syr 346 f. 59v:  After writing that the dragon Attalia does not exist but that eclipses only depend on the nodes ascending or descending from the moon (see the JA Sept-Oct. 1910 p. 219-224) he adds:  

[Syriac text]  .... |330 

The calculations with the help of which one finds these nodes (ascendant or descendant) exactly with their causes, are in the book which is named the Rule (canon) of calculations, made by the astronomer Ptolemy on the course and the movement of all the stars.  Although many men have preceded and followed him, he shines uniquely at the art of astronomy, more than all the ancients and moderns put together. It is following his thought that we are able to  determine the exact and true causes of eclipses, because we have taken a droplet of the great sea of sublime science that his works contain in order to start a discussion, i.e. a stimulant to the lovers of work (φιλόπονοι) so that they continue to apply themselves and do not relax their hunger for wisdom (φιλοσοφία), even though their adversaries scream at them and sharpen their words (against them).

We will stop our discourse here, while addressing with admiration to the |331 Creator of the Universe the words of the divine prophet, wise in all things:  Your works are large, O Lord, and that your thoughts are deep.  The stupid man knows nothing and the foolish man understands nothing.  

End of the treatise on:  What is the cause of eclipses of the stars (the Sun and the Moon) and that there is no Atalia (the celestial dragon) and from where the moon gets its light.  Made by the holy bishop Severus who is named Seboukt of Nisibis.

The enemies, to which Severus Sebokt has just referred, in the year 661, are neither the Arabs (who are still not writing) nor the Armenians, but the Greeks, because he returns to this subject in the following year (662) and attacks "those who believe that they alone have arrive at the limit of knowledge because they speak Greek"; he charges then the priest Basil with asking certain questions of the Greeks (of the island of Cyprus):  As a Syrian and an ignoramus, I transmit these small questions by your hands to those which believe that all science is in the Greek language. I request them to answer all these for me with care, cf.  ROC, vol.  XV, 1910, p. 250 and 252.

However we have already mentioned that in 659 Severus Sebokt, as an assistant to the monophysite patriarch Theodore, was defeated in a public discussion with "those of Beit-Maron".  And this discussion had had a painful continuation:  "The Jacobites were overcome and Moawiah condemned them to pay twenty thousand dinars, then he ordered to them to keep quiet; and the Jacobite bishops continued to pay every year the same amount of money to Moawiah so that he would not cease protecting them and that the sons of the Church could not persecute them." 4.  It seems possible that it is this failure of the year 659 which left Severus with so much rancour in 661 and 662. 

In this case his enemies would thus have been the Greeks, he would have been the assistant of the monophysite patriarch because of his knowledge of Greek, and those who are named the "people of Beit Maron" would be Greeks.  In fact the monothelite heresy was propagated and supported by the emperors of Constantinople, and so is a melkite heresy, since the name of Melkites was given to the partisans of the successive emperors.  |332 

It is possible that in the middle of the 7th century, after the period when so many monks had been dispossessed of their convents 5, that Beit Maron itself was for a time in the possession of monothelites melkites;  we do not know at what time the orthodox might have been driven out of it or returned there, we know less still what the relations of the monastery might be with the mountain dwellers of Lebanon. 

Here is another text of Severus against the Greeks to show that the Babylonians, i.e. the Syrians, who taught first the Egyptians and then the Greeks all that relates to astronomy (ms 346, fol.  168v-169): 

[Syriac text] |333 

That the Babylonians were Syrians, I believe that nobody will deny.  Consequently, they are greatly mistaken who say that it is not possible that the Syrians know something of such matters (astronomy), since these Syrians were the inventors and the first Masters in these matters.  Ptolemy again renders witness to this in the "Syntax"(Almageste), because when he chooses an origin for the computation of the Sun, the Moon and the five planets, he does not start with the years of Greek kings, but with those of the kings of Babylon, that is, Nebuchadnezzar, king of the Assyrians.  I said Nebuchadnezzar, not the one of whom the prophet Daniel was the contemporary, but another more ancient. Ptolemy has thus given in the "Syntax" that the years that have passed since this first Nebuchadnezzar ---- i.e. of the Babylonian and Persian kings ---- until Philip (Arrhidaeus) the Macedonian, the successor of Alexander the founder of Alexandria, (are in the number of) four hundred and twenty-four years 6.  There he rightly shows that he found among the Babylonians, and not among the Greeks, the beginning and foundation of the calculations which he made.  It is thus on this foundation that he built and that he piled up the many calculations that he made."

Biographical details on Severus Sebokht given by Ms. 346.

Here are all the titles which mention him and the details that he gives of his infirmities ca. 661-2 AD.

1.  The title of the treatise on the constellations (ms. 346, fol. 78r, cf. infra) 7 reads: 

[Syriac] |334 

Holy Severus, bishop of Qennesrin (Chalcis), who is named Sebokt, the Nisibite.

2. The end of the treatise (fol. 121v) reads:


(Treatise) which has been made by the holy (bishop) abbot Mar Severus Sebokt.  It has been written in the year 971 of the Greeks (661) in the third year of the indiction.  It has been written as the solution of questions and certain demands, coming from men who loved teaching, like that (addressed) to the friend of God, the priest and visitor Basil.

3.  The treatise on the astrolabe is older than the treatise on the constellations, which cites it twice (xv, 1; xvi, 5).  Thus it was written before 661.  It ends:


 Here ends the scholion on the astrolabe which was made by the abbot Mar Severus the Nisibite, i.e. Seboukht.

Here Severus does not have the title of bishop, but only of abbot (head of the convent).

4.  Chapter 19, which follows the treatise on the constellations and deals with the conjunctions of the planets, is addressed to the same Basil and ends:

[Syriac]  |335

When the planets will join together again is something that I have not been able to write now, because this requires a lot of work, and I am in great weakness from illness and also from old age.  I am lying on a bed because of the pain in my feet and, in truth, in all my members.  I cannot now apply myself to a calculation like that, and to very minute calculations, because in truth my spirit fails, and even as I write now, I write in great distress, very pressed as I was by the love of your spiritual Fraternity.

5. At the end of chapter 20, on predicting eclipses of the Moon and Sun, Severus again writes: 

[Syriac] |336 

As for the last question put by the noble man in question who loves Christ (Stephen, "illustrious" and chartulary of all Mesopotamia) that we give him an example (παραδείγμα) of the eclipse of the sun and that of the Moon, this was already done by many people, in particular by Theon, who we mentioned, in the commentary (σχόλιον) that he made on the manual tables (πρόχειρος)  (of Ptolemy) 8, (and) I hope that your Fraternity (Basil) ---- and by his intermediary the noble man mentioned ---- knows that I am in a great weakness, as the truth bears witness, and what I wrote, i.e. have written now, (I did) with much pain and lying in bed, with my feet extended because of illness, as his pure deacon, Mar Athanasius 9, who saw me with his own eyes, will be able to tell him, I |337 can do nothing of this sort today, firstly because I am alone in being able to take the trouble with such things and there is no-one else to help me in this, and this research demands much work and considerable spare time, although you perhaps think that it is as easy as the rest, finally because I am preparing at this moment to go to one of the hot springs which are here 10 because of the pain in my feet, or, more accurately (μᾶλλον δέ), of my whole body, which is aged, languishing and very weakened suddenly and without warning.   However if the Lord, by your prayers, gives me health, I am still willing to do this;  if you are (then) of this (world), (all will be) for the best; if not, if you are dead, let the abovementioned man be advised, and I will send this example about eclipses to him which I will make later if the Lord wishes. I propose this to reassure your Fraternity, but, for the moment, it is sufficient, I believe, and more than sufficient, because of my great weakness and exhaustion of spirit which affects me at the moment, as I have already said several times before. 

6. Another allusion to the illness of Severus is found at the end of the chapter on the climates, fol. 129 v.


I again write this (letter) warmly, although I am in great weakness, like I have already said; I write this lying on a bed because |338 of the pain in my feet and deprived of any human help, so to speak. And I do this, firstly because I am motivated by the spiritual charity which bears all things 11, which endures all things, to speak like the apostle (I Cor., xiii, 7), and then because I ask, as you also suggested, that you show these Greeks who glorify themselves as erudite in these things, that there have also been men among the Syrians who were versed in these matters.

7. In the year 662, Severus returns again to this last subject (fol. 170) and says that the Greeks learned astronomy from the Chaldaeans who are the Syrians.  He concludes from this that learning belongs to all and gives as an example the Hindus who have found a means of expressing all the numbers with nine signs.  This is here the oldest Eastern mention of the Indian figures, which we have published in Journal As., sept.-oct. 1910, p. 225-7.

Undoubtedly it will be thought strange that Severus of Qennesrin, to the south of Aleppo, and Basil of Cyprus make no allusion, around the year 661, to the conquest of Syria and of the island of Cyprus by the Arabs 12.  The reason is perhaps in the hostility of the Jacobites to the Greeks their persecutors;  for them the Arabs were liberators who spared them for a long time as they needed them 13.  It is this that explains why the 7th century was still a century of relative rest and great literary activity for the monophysite church. 


[Footnotes renumbered and moved to the end]

1. (1)  He could already have known the Persian language since there is attributed to him the translation from Persian into Syriac of a commentary on the Peri Hermenias composed by Paul the Persian.  Cf. JA Jul-Aug 1900 p.73.

2. (1)  However it is not impossible that the fragments on Gregory of Nazianzen in Ms. Add. 14517 (ff.236-240. Catalogue Wright....) also belong to Severus Sebokht, because they are attributed to "Severus ..." that is, not to "bishop of Nisibis" which would be different but to "Nisibite bishop" or "born in Nisibis" which is precisely the case of Sebokht. 

3. (2)  In this year, says the catalogue of Syriac manuscripts at Cambridge p.886 Heraclius came to Amida and from Amida descended to Babylon.  It is known at least that in that year the Arabs completed the conquest of Syria. 

4. (1) R.O.C., vol.  IV, 1899, p. 323.  We have given a reproduction of the syriaque text in Opuscules Maronites, first part, Paris, 1899, p. 39.

5. (1) cf Michael the Syrian, Chronicle, II, p. 412. 

6. (1)  The canon of Kings of Ptolemy begins with Nabonassar in 747 BC, mentions the Assyrian and Persian kings, and places Philippe Arrhidaeus in 324.  The difference is 423 years. 

7. (2) Between 661 and 1306, copying errors appear in the text, some letters are missing, others are changed. This can be seen by comparing certain transcriptions of the Greek either to the original, or with the way in which the same word is transcribed in other places in the manuscript.  An interesting fault is that which replaces the mountain of Crete Δίκτον by Riqton, because this fault also appears in Bar Hebraeus, Course of Astronomy, transl., p. 91, and show us that the scientist primate used, in 1279, a manuscript of Severus analogous to our own.

8. (2) On these tables, see note below, xiv, 10.

9.  (3) Perhaps Athanasius of Balad, which is given as a pupil of Severus in Qennesrin, who then lived at the convent of Beit Malka in Tur'Abdin  and who was named patriarch in 995 (681). Cf Michael, Chronicle, II, 471;  Bar Hebraeus, Chron. eccl., I, 287-9.

10. (1) Severus seems to be saying that there are thermal waters not far from Aleppo.  Indeed in Rahmani, Chronicon civil Ecclesiasticum, Scharfé, 1901, p:  128, Magnus, curator and general, goes to Edessa to hot springs which are in a village not far from Emesa.  ---- The Father F.M. Abel signalled those which exist close to the Dead Sea, cf.  Une croisière autour de la mer Morte (=A cruise around the Dead Sea),Paris, 1911, p. 22, 27, 42, 66.

11. (1) The Peshitto reads [Syriac] omnia sperat. 

12. (2) Moawiah had conquered Cyprus as of 648.

13. (3) Perhaps it is necessary to see an effect of the devastations caused in Syria by the Persians and the Arabs when Severus "bishop of Qennesrin" :  writes, "I am ill … there is nobody else here to help me in this... deprived of any human help so to speak."  

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