Samuel told him every whit - Our word whit, or wid, comes from the Anglo-Saxon, which signifies person, thing, etc.; every whit is every thing. The Hebrew הדברים כל את et col haddebarim, "all these words."
It is the Lord - He is Sovereign, and will do what he pleases; he is righteous, and will do nothing but what is just.
Let him do what seemeth him good - There is much of a godly submission, as well as a deep sense of his own unworthiness, found in these words. He also had sinned, so as to be punished with temporal death; but surely there is no evidence that the displeasure of the Lord against him was extended to a future state.
It is the Lord - Compare the devout submission of Aaron Leviticus 10:3, and of Hezekiah 2 Kings 20:19. And, for the highest conceivable submission to the will of God, compare Luke 22:42.