'I Am the Lord' in the Bible

And behold, there came a prophet to Ahab king of Israel, saying, Thus saith the LORD, Hast thou seen all this great multitude? behold, I will deliver it into thy hand this day; and thou shalt know that I am the LORD.

And there came a man of God, and spoke to the king of Israel, and said, Thus saith the LORD, Because the Syrians have said, The LORD is God of the hills, but he is not God of the valleys, therefore will I deliver all this great multitude into thy hand, and ye shall know that I am the LORD.