1 Samuel 17:29 - Joseph Benson’s Commentary on the Old and New Testaments

David said, Is there not a cause? Of my thus speaking? Is this giant invincible? Is our God unable to oppose him, and subdue him? However, David is not deterred from his undertaking by the hard words of Eliab. They that undertake public services must not think it strange if they be opposed by those from whom they had reason to expect assistance; but must humbly go on with their work, in the face, not only of their enemies' threats, but of their friends' slights, suspicions, and censures.