'Letters' in the Bible

He asked him for letters to take with him to the synagogues in Damascus, so that if he found any men or women belonging to the Way, he might bring them in chains to Jerusalem.

as the high priest and the whole council of elders can testify about me. I also received letters from them to the brothers in Damascus, and I was going there to tie up those who were there and bring them back to Jerusalem to be punished.

The Jewish leaders told him, "We haven't received any letters from Judea about you, and none of the brothers coming here has reported or mentioned anything bad about you.