John Gill Commentary Ezekiel 16:48

"As I live, saith the Lord Jehovah, Sodom thy sister hath not done, she nor her daughters, as thou hast done, thou and thy daughters." — Ezekiel 16:48 (ASV)

[As] I live, says the Lord God
This is an oath, which the Lord God swore; who, because he could swear by no greater, he swore by himself, by his life; and this he did to confirm what he had and was about to say, that the sins of Judah were greater than those of Samaria and Sodom; which might not be easily believed, but it was as true as he was the living God: Sodom your sister has, or done, she nor her daughters, as you have
done, you and your daughters ;
that is, the inhabitants of Sodom, and of the villages adjacent, as the Targum, had not committed such gross iniquities as the inhabitants of Jerusalem, and of the towns and villages about it, and of other cities of Judah.