'Letters' in the Bible

and asked of him letters to Damascus, to the synagogues, so that if he found any who were of the way, both men and women, he might bring them bound to Jerusalem.

as also the high priest bears me witness, and all the elderhood: from whom also, having received letters to the brethren, I went to Damascus to bring those also who were there, bound, to Jerusalem, to be punished.

And they said to him, For our part, we have neither received letters from Judaea concerning thee, nor has any one of the brethren who has arrived reported or said anything evil concerning thee.