1 Samuel 17:37 - Ellicott's Commentary On The Whole Bible

Go, and the Lord be with thee. — This permission and blessing of King Saul recalls the Saul of old days, before the covenant between him and the Mighty One of Israel was broken, before the Spirit of the Lord had departed from him. It was a great act of courageous trust in the Glorious Arm which had, Saul knew, so often fought for Israel. We must bear in mind that it was no mere duel between two fighting men, an Israelite and a Philistine, but that the fortunes of the nation for an indefinite period were to be staked on this momentous single combat between a tried warrior of gigantic strength and a boy quite unaccustomed to martial exercises, and, as we shall presently see, a stranger even to a soldier’s dress and martial equipment.