Exodus 3:14 in the King James Version
And God said unto Moses, I AM THAT I AM: and he said, Thus shalt thou say unto the children of Israel, I AM hath sent me unto you.
Context
13 Moses said to God, “Behold, when I come to the children of Israel, and tell them, ‘The God of your fathers has sent me to you,’ and they ask me, ‘What is his name?’ what should I tell them?”
14 God said to Moses, “I AM WHO I AM,” and he said, “You shall tell the children of Israel this: ‘I AM has sent me to you.’”
15 God said moreover to Moses, “You shall tell the children of Israel this, ‘The LORD, the God of your fathers, the God of Abraham, the God of Isaac, and the God of Jacob, has sent me to you.’ This is my name forever, and this is my memorial to all generations.