He; either, first, Amasa, by his great influence upon them. Or rather, secondly, David, by his prudent and kind message, and his free offer of pardon and favour to them, as if they had never offended.
Related Commentaries of 2 Samuel 19:14
2 Samuel 19:14
14 And he bowed the heart of all the men of Judah, even as the heart of one man; so that they sent this word unto the king, Return thou, and all thy servants.