“For three transgressions of the children of Ammon, yes, for four.” The poetic expression “three…four” is an idiom for “many.” The Ammonites were a rather constant adversary to Israel, in spite of being descendants of Abraham’s nephew Lot. Nahash the Ammonite tried to take territory from Israel and humiliate God’s people (1 Sam. 11:1-2). Hanun the Ammonite humiliated David’s ambassadors (2 Sam. 10:1-4). And the trouble continued after the time of Amos. For example, Tobiah the Ammonite was an adversary to Israel in the time of Nehemiah (Neh. 2:10, 19; 4:3, 7; 6:12-14), and Baalis the king of Ammon hired a man to kill the Babylonian provisional governor of Judah after the Babylonian destruction of the country (Jer. 40:14).