I have not proved them; I have no skill nor experience in the management of this kind of arms.
Related Commentaries of 1 Samuel 17:39
1 Samuel 17:39
39 And David girded his sword upon his armour, and he assayed to go; for he had not proved it. And David said unto Saul, I cannot go with these; for I have not proved them. And David put them off him.