'Letters' in the Bible

did ask from him letters to Damascus, unto the synagogues, that if he may find any being of the way, both men and women, he may bring them bound to Jerusalem.

as also the chief priest doth testify to me, and all the eldership; from whom also having received letters unto the brethren, to Damascus, I was going on, to bring also those there bound to Jerusalem that they might be punished,

And they said unto him, 'We did neither receive letters concerning thee from Judea, nor did any one who came of the brethren declare or speak any evil concerning thee,