Why did God use the little shepherd boy David instead of King Saul?
God chose David instead of King Saul because Saul was a proud individual, impressive in appearance and military talent, yet he amounted to nothing. The little shepherd boy David had no status to claim, and God uses the humble, lowly nobody rather than the proud person who trusts in himself.
Les explains the same pattern with Moses, Saul, and David. King Saul was proud, the best-looking young man around, with military talent, but he didn't amount to a hill of beans. God finally used the little shepherd boy David. Earlier, Moses spent 40 years herding sheep on the back side of the desert, with no contact with big population centers; when God called him, Moses said, "Lord, I can't. I'm a nobody. I can't talk." That is where God wanted him. Likewise, Saul of Tarsus was a big man in Judaism, profiting in the Jews' religion and in the upper echelons, so God couldn't use him from there. God put him down on the road to Damascus as a nobody, trembling and astonished, asking, "Lord, what would you have me to do?" God then used Ananias as a go-between. The lesson is that God uses those brought low, not the proud and self-sufficient.