Acts 15:22, 30-32, 36-40

Then it seemed good to the apostles and the elders, with the whole church, to choose men out of their company, and send them to Antioch with Paul and Barnabas; namely, Judas called Barsabbas, and Silas, chief men among the brethren

So they, when they were dismissed, came down to Antioch; and having gathered the multitude together, they delivered the epistle. And when they had read it, they rejoiced for the consolation. And Judas and Silas, being themselves also prophets, exhorted the brethren with many words, and confirmed them.

And after some days Paul said unto Barnabas, Let us return now and visit the brethren in every city wherein we proclaimed the word of the Lord, and see how they fare. And Barnabas was minded to take with them John also, who was called Mark. But Paul thought not good to take with them him who withdrew from them from Pamphylia, and went not with them to the work. And there arose a sharp contention, so that they parted asunder one from the other, and Barnabas took Mark with him, and sailed away unto Cyprus: but Paul chose Silas, and went forth, being commended by the brethren to the grace of the Lord.