1 Samuel 14:8-10

Then said Jonathan, Behold, we will pass over unto these men, and we will discover ourselves unto them.

If they say thus unto us, Tarry until we come to you; then we will stand still in our place, and will not go up unto them.

But if they say thus, Come up unto us; then we will go up: for the LORD hath delivered them into our hand: and this shall be a sign unto us.