Acts 9:22

But Saul increased the more in strength
Not of body, but of mind; his gifts and graces, and spiritual light and knowledge increased; his abilities were greater; his fortitude of mind, boldness, and freedom of speech, every day increased: he got more, and new, and fresh arguments, by which he himself was confirmed, and he confirmed others in the truths of Christ. Some copies read, "he was more strengthened in the word"; either in the word of God, having a clearer understanding, and being more confirmed in the truth of it; or in speech, being more ready and powerful in speaking it.

And confounded the Jews which dwelt at Damascus;
confuted them, and put them to silence, so that they had nothing to say for themselves, or against the truth:

proving that this is very Christ;
by joining and knitting passages of Scripture in the Old Testament together, by producing and citing express testimonies from thence, and by comparing the prophecies and the characters of the Messiah in them, with Jesus of Nazareth, he proved to a demonstration that he must be the Messiah.