1 Samuel 18:1-3

And it cometh to pass, when he finisheth to speak unto Saul, that the soul of Jonathan hath been bound to the soul of David, and Jonathan loveth him as his own soul. And Saul taketh him on that day, and hath not permitted him to turn back to the house of his father. And Jonathan maketh — also David — a covenant, because he loveth him as his own soul