'It is I' in the Bible

For all of them saw him, and were terrified. But Jesus at once spoke to them. "Courage!" he said, "it is I; do not be afraid!"

But, when Jesus saw that a crowd was quickly collecting, he rebuked the foul spirit: "Deaf and dumb spirit, it is I who command you. Come out from him and never enter him again."

Jesus looked at them, and answered: "With men it is impossible, but not with God; for everything is possible with God."