Acts 22:5

The high priest doth bear me witness, etc. - He probably referred to the letters of authority which he had received from the high priest, and the whole estate of the elders, παν το πρεσβυτεριον , the whole of the presbytery, that is, the sanhedrin; and it is likely, that he had those letters to produce. This zeal of his against Christianity was an ample proof of his sincerity as a Pharisaical Jew.