Died about 346. The main facts of his life will be found in MONASTICISM (Section II: Eastern Monasticism before Chalcedon). Having spent some time with Palemon, he went to a deserted village named Tabennisi, not necessarily with the intention of remaining there permanently. A hermit would often withdraw for a time to some more remote spot in the desert, and afterwards return to his old abode. But Pachomius never returned; a vision bade him stay and erect a monastery; "very many eager to embrace the monastic life will come hither to thee". Although from the first Pachomius seems to have realized his mission to substitute the cenobitical for the eremitical life, some time elapsed before he could realize his idea. First his elder brother joined him, then others, but all were bent upon pursuing the eremitical life with some modifications proposed by Pachomius (e.g., meals in common). Soon, however, disciples came who were able to enter into his plans. In his treatment of these earliest recruits Pachomius displayed great wisdom. He realized that men, acquainted only with the eremitical life, might speedily become disgusted, if the distracting cares of the cenobitical life were thrust too abruptly upon them. He therefore allowed them to devote their whole time to spiritual exercises, undertaking himself all the burdensome work which community life entails. The monastery at Tabennisi, though several times enlarged, soon became too small and a second was founded at Pabau (Faou). A monastery at Chenoboskion (Schenisit) next joined the order, and, before Pachomius died, there were nine monasteries of his order for men, and two for women.
How did Pachomius get his idea of the cenobitical life? Weingarten (Der Ursprung des Möncthums, Gotha, 1877) held that Pachomius was once a pagan monk, on the ground that Pachomius after his baptism took up his abode in a building which old people said had once been a temple of Serapis. In 1898 Ladeuze (Le Cénobitisme pakhomien, 156) declared this theory rejected by Catholics and Protestants alike. In 1903 Preuschen published a monograph (Möncthum und Serapiskult, Giessen, 1903), which his reviewer in the "Theologische Literaturzeitung" (1904, col. 79), and Abbot Butler in the "Journal of Theological Studies" (V, 152) hoped would put an end to this theory. Preuschen showed that the supposed monks of Serapis were not monks in any sense whatever. They were dwellers in the temple who practised "incubation", i.e. sleeping in the temple to obtain oracular dreams. But theories of this kind die hard. Mr. Flinders Petrie in his "Egypt in Israel" (published by the Soc. for the Prop. of Christ. Knowl., 1911) proclaims Pachomius simply a monk of Serapis. Another theory is that Pachomius's relations with the hermits became strained, and that he recoiled from their extreme austerities. This theory also topples over when confronted with facts. Pachomius's relations were always affectionate with the old hermit Palemon, who helped him to build his monastery. There was never any rivalry between the hermits and the cenobites. Pachomius wished his monks to emulate the austerities of the hermits; he drew up a rule which made things easier for the less proficient, but did not check the most extreme asceticism in the more proficient. Common meals were provided, but those who wished to absent themselves from them were encouraged to do so, and bread, salt, and water were placed in their cells. It seems that Pachomius found the solitude of the eremitical life a bar to vocations, and held the cenobitical life to be in itself the higher (Ladeuze, op. cit., 168). The main features of Pachomius's rule are described in the article already referred to, but a few words may be said about the rule supposed to have been dictated by an angel (Palladius, "Hist. Lausiaca", ed. Butler, pp. 88 sqq.), of which use is often made in describing a Pachomian monastery. According to Ladeuze (263 sqq.), all accounts of this rule go back to Palladius; and in some most important points it can be shown that it was never followed by either Pachomius or his monks. It is unnecessary to discuss the charges brought by Amelineau on the flimsiest grounds against the morality of the Pachomian monks. They have been amply refuted by Ladeuze and Schiwietz (cf. also Leipoldt, "Schneute von Atripe", 147).
In addition to the bibliography already given (Eastern Monasticism before Chalcedon) consult CABROL, Dict. d'archeol. chret., s.v. Cenobitisme; BOUSQUET AND NAU, Hist. de S. Pacomus in Ascetica. . .patrologia orient., IV (Paris, 1908).