Flavius Josephus, Antiquities of the Jews
William Whiston, A.M., Ed.

[18] Now although they suggested these arguments to him for his own advantage, yet did Hyrcanus still desire to depart. Herod also wrote to him, and persuaded him to desire of Phraates, and the Jews that were there, that they should not grudge him the royal authority, which he should have jointly with himself, for that now was the proper time for himself to make him amends for the favors he had received from him, as having been brought up by him, and saved by him also, as well as for Hyrcanus to receive it. And as he wrote thus to Hyrcanus, so did he send also Saramallas, his ambassador, to Phraates, and many presents with him, and desired him in the most obliging way that he would be no hinderance to his gratitude towards his benefactor. But this zeal of Herod's did not flow from that principle, but because he had been made governor of that country without having any just claim to it, he was afraid, and that upon reasons good enough, of a change in his condition, and so made what haste he could to get Hyrcanus into his power, or indeed to put him quite out of the way; which last thing he compassed afterward.