The Ammonites took the land of Gad and possessed it with their god Malcam (Jer. 49:1).
Jeremiah 49:2a and 3 tell us that Jehovah would cause war against the Ammonites. Their nation would become a mound of desolation, and its villages would be burned with fire. Their god Malcam would go into exile together with its priests and its princes.
Regarding the Ammonites, we are told that Israel will dispossess those who dispossess him (v. 2b; cf. Zeph. 2:8-9; Amos 1:13-15).
Jeremiah 49:6 prophesies that afterward Jehovah will turn again the captivity of the children of Ammon.
The word in 49:7-22 concerns Jehovah's punishment and judgment upon Edom.
Edom was a nation of the descendants of Esau, who was the twin brother of Jacob; who was hated by God and destined by God to serve his younger brother; and who was struggling in the flesh against his brother (Gen. 36:9; 25:21-26a; Mal. 1:3a; Rom. 9:13b; 1 Kings 11:14-16; 2 Kings 8:20, 22; Psa. 83:4-6; 137:7; Num. 20:21). As such a nation, Edom typifies the world of the old and fleshly man who struggles against the God-chosen and spiritual people.