Albert Barnes on Acts 22:18

And saw him. Evidently the Lord Jesus, Acts 22:14. He had received his commission from him, and he now received a distinct command to go to the Gentiles.

For they will not receive. The inhabitants of Jerusalem, probably including both Jews and Christians. The Jews would not listen to him, because he had become, in their view, an apostate, and they would hate and persecute him. The Christians would not be likely to receive him, for they would remember his former persecutions, and would be suspicious of him, because he had been so long in Arabia, and had not sooner connected himself with them. Acts 9:26, "And when Saul was come to Jerusalem, he assayed to join himself to the disciples; but they were all afraid of him, and believed not that he was a disciple."

(h) "saw him" Acts 7:58