1 Samuel 20:3-4

And David sware moreover, and said, Thy father certainly knoweth that I have found grace in thine eyes; and he saith, Let not Jonathan know this, lest he be grieved: but truly as the LORD liveth, and as thy soul liveth, there is but a step between me and death. Then said Jonathan unto David, Whatsoever thy soul desireth, I will even do it for thee.