John Calvin on Acts 9:27

27. When Barnabas had taken him. Whereas the disciples fled so fast from Paul, that was, peradventure, a point of too great fearfulness, “Id nimiae forsan timiditatis fuit,” that, perhaps, was owing to too great timidity. and yet he speaketh of none of the common sort, but of the apostles themselves. But he doth either extenuate or lighten their fault, because they suspected him for just causes, whom they had found and tried “Experti sunt,” experienced. to be such a deadly enemy; and, it was to be feared, lest they should rashly endanger themselves if they should have showed themselves to be so easy to entreat. Therefore, I think that they are not to be blamed for that fear which they conceived for just cause, or that they deserve to be even accused for the same. For if they had been called to give an account of their faith, they would have provoked “Provocassent,” challenged or defied. not Paul only, but also all the furies of hell, without fear. Whence we gather that every fear is not to be condemned but such as causeth us to turn aside from our duty. The narration which Luke addeth may be referred as well unto the person of Barnabas as of Paul. Yet I think rather that Paul declareth to the apostles what had befallen him; and yet the speech may be well applied to Barnabas, especially when as mention is made of Paul’s boldness.