Ezekiel 9:4-6

4And the Lord said to him, "Pass through the city, through Jerusalem, and put a mark on the foreheads of the men who sigh and groan over all the abominations that are committed in it."

5And to the others he said in my hearing, "Pass through the city after him, and strike. Your eye shall not spare, and you shall show no pity.

6Kill old men outright, young men and maidens, little children and women, but touch no one on whom is the mark. And begin at my sanctuary." So they began with the elders who were before the house.