1 Samuel 20:39

And David fled from Naioth in Ramah, and came and said before Jonathan, What have I done? what is mine iniquity? and what is my sin before thy father, that he seeketh my life?

And he said unto him, God forbid; thou shalt not die: behold, my father will do nothing either great or small, but that he will shew it me: and why should my father hide this thing from me? it is not so.

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.