Even for a whole year (kai eniauton holon). Accusative of extent of time, probably the year a.d. 44, the year preceding the visit to Jerusalem (Act 11:30), the year of the famine. The preceding years with Tarsus as headquarters covered a.d. 37 (39) to 44.
They were gathered together with the church (sunachthēnai en tēi ekklēsiāi). First aorist passive infinitive of sunagō, old verb, probably here to meet together as in Mat 28:12. In Act 14:27 the verb is used of gathering together the church, but here en tēi ekklēsiāi excludes that idea. Barnabas met together “in the church” (note first use of the word for the disciples at Antioch). This peculiar phrase accents the leadership and co-operation of Barnabas and Saul in teaching (didaxai, first aorist active infinitive) much people. Both infinitives are in the nominative case, the subject of egeneto (it came to pass).
And that the disciples were called Christians first in Antioch (chrēmatisai te prōtōs en Antiocheiāi tous mathētas Christianous). This first active infinitive chrēmatisai is also a subject of egeneto and is added as a separate item by the use of te rather than kai. For the word itself in the sense of divine command, see note on Mat 2:12, note on Mat 2:22; note on Luk 2:26; and note on Act 10:22. Here and in Rom 7:3 it means to be called or named (assuming a name from one’s business, chrēma, from chraomai, to use or to do business). Polybius uses it in this sense as here. Tous mathētas (the disciples) is in the accusative of general reference with the infinitive. Christianous (Christians) is simply predicate accusative. This word is made after the pattern of Herodianus (Mat 22:16, Herōidianoi, followers of Herod), Caesarianus, a follower of Caesar (Deissmann, Light from the Ancient East, p. 377, gives papyri examples of the genitive Kaisaros meaning also “belonging to Caesar” like the common adjective Caesarianus). It is made thus like a Latin adjective, though it is a Greek word, and it refers to the Hebrew belief in a Messiah (Page). The name was evidently given to the followers of Christ by the Gentiles to distinguish them from the Jews since they were Greeks, not Grecian Jews. The Jews would not call them Christians because of their own use of Christos the Messiah. The Jews termed them Galileans or Nazarenes. The followers of Christ called themselves disciples (learners), believers, brethren, saints, those of the Way. The three uses of Christian in the N.T. are from the heathen standpoint (here), Act 26:28 (a term of contempt in the mouth of Agrippa), and 1Pe 4:16 (persecution from the Roman government). It is a clear distinction from both Jews and Gentiles and it is not strange that it came into use first here in Antioch when the large Greek church gave occasion for it. Later Ignatius was bishop in Antioch and was given to the lions in Rome, and John Chrysostom preached here his wonderful sermons.