Amaziah ... did that which was right in the sight of the LORD, but not with a perfect heart. 2 Chronicles 25.1-2And the first thing that he did was murder the murderers of his father.
Now it came to pass, when the kingdom was established to him, that he slew his servants that had killed the king his father. 25.3Next he killed 10,000 Edomites (children of Seir).
Amaziah strengthened himself, and led forth his people, and went to the valley of salt, and smote of the children of Seir ten thousand. 25.11And then he rounded up another 10,000 Edomites and pushed them all off a cliff. And "they all were broken in pieces."
And other ten thousand left alive did the children of Judah carry away captive, and brought them unto the top of the rock, and cast them down from the top of the rock, that they all were broken in pieces. 25.12But then, after he got back from slaughtering the Edomites, Amaziah began to worship the Edomite gods.
After that Amaziah was come from the slaughter of the Edomites, that he brought the gods of the children of Seir, and set them up to be his gods, and bowed down himself before them, and burned incense unto them. 25.14Which, unlike throwing 10,000 people off a cliff, was not right in the eyes of the Lord.
So God sent a prophet to tell Amaziah that God was going to destroy him.
Wherefore the anger of the LORD was kindled against Amaziah, and he sent unto him a prophet, which said unto him ... God hath determined to destroy thee. 25.15-16Next Amaziah had a meeting with king Joash of Israel, who has this to say to Amaziah:
The thistle that was in Lebanon sent to the cedar that was in Lebanon, saying, Give thy daughter to my son to wife: and there passed by a wild beast that was in Lebanon, and trode down the thistle. 25.18Which means nothing at all to me.
But then Joash says something a bit more comprehensible.
Thou sayest, Lo, thou hast smitten the Edomites; and thine heart lifteth thee up to boast: abide now at home; why shouldest thou meddle to thine hurt, that thou shouldest fall, even thou, and Judah with thee? 25.19Which means, I guess, "Back off, big guy."
But Amaziah didn't back off and Joash defeated him ("for it came of God").
But Amaziah would not hear; for it came of God, that he might deliver them into the hand of their enemies, because they sought after the gods of Edom. ... And Judah was put to the worse before Israel. 25.20-22Although Amaziah's army was defeated by Joash's, Amaziah survived the battle. But years later there was a conspiracy against him and he was killed.
Now after the time that Amaziah did turn away from following the LORD they made a conspiracy against him in Jerusalem; and he fled to Lachish: but they sent to Lachish after him, and slew him there. 25.27So God caused the death of Amaziah and the defeat of his army, and, therefore the death of many of his soldiers. So I’ll add another 1000 to God’s total.
God's next killing: Ahaz