John Wesley on 1 Samuel 16:21

Stood before him - That is, waited upon him. And he loved him greatly - So there was something good in Saul still: he had not lost all, tho' he had lost the kingdom. Armour - bearer - He had that place conferred upon him, though we do not read that he ever exercised it; for it seems he was gone back to his father upon some occasion not related; and had abode with him some considerable time before the war described, chap.17:1 - 53, happened.