On Theodore see Amelineau, S. Pakhôme, &c., pp. xcv.–xcvii. The death of Theodore is fixed for April 27, 364, on the following grounds. He died (Vit. Pachom. 95) of a short and sudden illness, on Pachon 2 (April 27), and shortly after Easter. Moreover his death took place 18 years after that of Pachomius. But Ammon (as he tells us himself, supr. p. 487) became a Christian and a monk ‘a year and more’ after March 15, 351 (proclamation of Gallus as Cæsar), and six years after the death of Pachomius. (Ep. Amm. 4, 5.) This dates the latter event a little less than five years before March 15, 351. But Pachomius died, according to his Life, on Pachon 14 (May 9), of an epidemic which attacked the community after Easter. This double condition is satisfied by the year 346, in which Easter fell on Pharm. 4, forty days before the day of Pachomius’ decease. If then Pachomius died in 346, Theodore died in 364. Against this result we have (1) the fact that in that year April 27 was twenty-three days after Easter; but the Easter gathering of the monks would last over April 11 (Low Sunday), and the death of Theodore would come suddenly enough a fortnight later; (2) the fragment (supr. p. 551) probably belonging to Letter 39, which a coptic life of Theodore makes him state that he received before his last Easter. But this cannot be correct; for all known data forbid us to place the death of Theodore as late as 367. (Tillemont’s tentative opinion, vii. 691, 761, is bound up with an obsolete chronology of the exiles of Athan.) On the other hand Theodore cannot have died as early as 363. Athanasius was with him (supr. p. 487) in the summer of that year, and when our present letter was written Ath. had clearly kept Easter at home, which suits 364, but excludes 363.
Editorial footnote · Personal Letters (Robertson translation), Letter 58, editorial note cite_note-1 · Original source