He adds also, they should testify, &c.: the apostles, and their successors, by the preaching of the gospel; but particularly the apostles, Acts 10:39 1 John 1:2,3, being chosen witnesses, Acts 10:41. And they were competent witnesses, because they had been with Christ from the beginning of his public ministry. We shall find the testimony of his apostles and of the Holy Ghost both joined together, Acts 5:32.
Related Commentaries of John 15:27
John 15:27
27 And ye also shall bear witness, because ye have been with me from the beginning.