John Gill Commentary Ezekiel 5:11

"Wherefore, as I live, saith the Lord Jehovah, surely, because thou hast defiled my sanctuary with all thy detestable things, and with all thine abominations, therefore will I also diminish [thee]; neither shall mine eye spare, and I also will have no pity." — Ezekiel 5:11 (ASV)

Wherefore, [as] I live, says the Lord God
This is a form of an oath, and shows that what is after said should certainly be done; God would not repent of it, nor revoke it: surely, because you have defiled my sanctuary, with all your detestable
things, and with all your abominations :
that is, with their idols and idolatrous worship, which were detestable and abominable to the Lord; so Manasseh not only built altars for Baal in the house of the Lord, but set up in it a graven image of the grove, (2 Kings 21:3 2 Kings 21:4 2 Kings 21:7) ; therefore will I also diminish [you] ;
as they lessened his glory by such abominable actions, so he threatens that he would lessen their privileges and blessings; as they took away from him the worship and honour that were due to him, so he would take away from them their civil and church state, his sanctuary, word, and ordinances, and deprive them of everything that was valuable and excellent. The Targum paraphrases it, "I will cut off the strength of your arm;" weaken her power: neither shall my eye spare, neither will I have any pity ;
when in the greatest misery and distress. The Targum is, "my Word shall not spare".