“And when the words were heard which David spake, they rehearsed them before Saul: and he sent for him.”
King James Version (KJV)
17:29 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.
17:30 He tarried - For being secretly moved by God's spirit to undertake the combat. He speaks with divers persons about it, that it might come to the king's ear.
17:32 Let no man's heart, &c. - It would have reflected upon his prince to say, Let not thy heart fail: therefore he speaks in general terms, Let no man's heart fail. A little shepherd, come but this morning from keeping sheep, has more courage than all the mighty men of Israel! Thus doth God often do great things for his people by the weak things of the world.
17:33 A youth - Not above 20 years old; and a novice, a raw and unexperienced soldier.