1 Samuel 20:3 KJV
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.
1 Samuel 20:3, King James Version
In context
2 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.
3 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.
4 Then said Jonathan unto David, Whatsoever thy soul desireth, I will even do it for thee.