'It is I' in the Bible

“But if the prophet is prevailed upon to speak a word, it is I, the Lord, who have prevailed upon that prophet, and I will stretch out My hand against him and destroy him from among My people Israel.

Behold, while it is intact, it is not made into anything. How much less, when the fire has consumed it and it is charred, can it still be made into anything!

You will fall on the open field; for it is I who have spoken,” declares the Lord God.