“Then the glory of the God of Israel rose from above the cherub where it had been, to the threshold of the temple. He called to the man clothed in linen with the writing equipment at his side. “Pass throughout the city of Jerusalem,” the Lord said to him, “and put a mark on the foreheads of the men who sigh and groan over all the detestable practices committed in it.” He spoke as I listened to the others, “Pass through the city after him and start killing; do not show pity or spare them! Slaughter the old men, the young men and women, as well as the older women and little children, but do not come near anyone who has the mark. Now begin at My sanctuary.” So they began with the elders who were in front of the temple.”
Ezekiel 9:3-6 HCSB
I see this as God’s way of telling me that being righteous in God’s sight is not only refraining from evil and wickedness, but also being grieved over those who don’t. This is being zealous for Him and His ways.