Translated by Cardinal Newman.
The word 'tome' (tomos) means either a section, or, in the case of such a document as that before us, a concise statement. It is commonly applied to synodical letters (cf. the 'Tome' of Leo, a.d. 450, to Flavian).
Upon the accession of Julian (November, 361) the Homoean ascendancy which had marked the last six years of Constantius collapsed. A few weeks after his accession (Feb. 362) an edict recalled all the exiled Bishops. On Feb. 21 Athanasius re-appeared in Alexandria. He was joined there by Lucifer of Cagliari and Eusebius of Vercellae, who were in exile in Upper Egypt. Once more free, he took up the work of peace which had busied him in the last years of his exile (see Prolegg. ch. ii. S:9). With a heathen once more on the throne of the Caesars, there was everything to sober Christian party spirit, and to promise success to the council which met under Athanasius during the ensuing summer. Among the twenty-one bishops who formed the assembly the most notable are Eusebius of Vercellae, Asterius of Petra, and Dracontius of Lesser Hermopolis and Adelphius of Onuphis, the friends and correspondents of Athanasius. The rest, with the exception of Anatolius of Euboea, were all from Egypt and Marmarica, and (probably three only) from S.W. Asia. The council (Newman, Arians, v. i.; Gwatkin, Stud. p. 205, Krueger, Lucif. 45-53, was occupied with four problems: (1) The terms on which communion should be vouchsafed to those Arians who desired to re-unite (S:S:3, 8). They were to be asked for nothing beyond the Nicene test, and an express anathema against Arianism, including the doctrine that the Holy Spirit is a Creature. The latter point had been rising into prominence of late, and had called forth from Athanasius his four Discourses to Serapion of Thmuis. The emphatic way in which the point is pressed in S:3, implies that an attempt was being made in some quarter to subscribe the Nicene Creed, while maintaining the Arian position with regard to the Holy Spirit. The language of S:3 cannot be reconciled with the hypothesis (Gwatkin, Studies, 233), that no formal requirement was made by this council on the subject. The person aimed at was possibly Acacius, who (Serap. iv. 7) had treated the subject with levity, and yet was now disposed to come to terms (as he did a year later, Socr. iii. 25). It is true that we find the names of Macedonius and his followers (N.B. not Eleusius) in the number of the 59 who betook themselves to Liberius (Socr. iv. 12), and neither in their letter nor in his reply is there any allusion to the doctrine of the Holy Spirit; and that Basil (Ep. 204), with the sanction of Athanasius (cf. below, Letters 62, 63), did not press the test upon those who were otherwise orthodox. But the council of 362 has Syrian circumstances specially in view; and however we may explain it, its language is too clear to be mistaken. (On the general subject, cf. Letter 55.) (2) The Arian Christology also occupied the council (S:7). The integrity of Christ's human nature on the one hand, its perfect Union with the Word on the other, are clearly emphasised. This question had begun to come into prominent discussion in several parts of the Christian world (e.g. at Corinth, see infr. Letter 59), and was soon to give rise to the system of Apollinarius, who, however, it is interesting to note, was a party, by his legates, to the present decision. (3) The state of the Church at Antioch was the most practical problem before the council. Meletius was returning to the presidency of the main body of the Antiochene church, whose chief place of worship was the 'Palaea' (S:3). Since the deposition of Eustathius (c. 330), the intransigent or 'protestant' body had been without a bishop, and were headed by the respected presbyter Paulinus. Small in numbers, and dependent for a church upon the good will of the Arians, they were yet strong in the unsullied orthodoxy of their antecedents, in the sympathy of the West and of Athanasius himself, who had given offence at Antioch in 346 by worshipping with them alone. Clearly the right course was that they should reunite with the main body under Meletius, and this was what the council recommended (S:3), although, perhaps in deference to the more uncompromising spirits, the union is treated (ib. and 4) as a return of the larger body to the smaller, instead of vice versa. (For the sequel, see Prolegg. ubi supra.)
Reference address : https://www.elpenor.org/athanasius/letter-antioch.asp