Then he took his staff in his hand; and he chose for himself five smooth stones from the brook, and put them in a shepherd's bag, in a pouch which he had, and his sling was in his hand. And he drew near to the Philistine. (1 Samuel 17:40)
In the Name + of Jesus. Amen. Five smooth stones. To sling against the giant, Goliath. No sword. No armor. No helmet. Just the little weapon that a shepherd might use to scare off a wolf from messing with the sheep. And one of those stones found a place in Goliath's head, taking down the mocking enemy of Israel.
The Son of David. Jesus. Five wounds in hands and feet and side. He takes down the Goliath of sin, death and devil. The enemies of the Lord can't stand against the pierced Jesus who gives His life for sinners. Sin, death, devil and hell are laid low by the Son of God and Son of David whose five wounds spell the end of their power and strength.
And now, five stones for you. Baptism, Absolution, the Word, body and blood. Five gifts of Jesus by which you cast down sin, death and devil, laying low the enemies which would destroy you.
These enemies look big. Impressive even. Scary. The whole army of Israel sat and cowered as Goliath came out day after day to mock them. They trembled in their sandals and armor and there was no way they could defeat him. But David didn't trust in Himself. He knew the Lord was more powerful than Goliath. Don't fear your sins. Don't fear death or the devil. He who fights for you is mightier than they are. He is the Son of David whose death and resurrection defeat all your enemies.
It's foolish to think we can overcome these things on our own. Being a Christian isn't some self-help program whereby we gain confidence to confront the things that attack us. Rather, being a Christian means you have Christ fighting for you to save and rescue you from all your enemies. Your own sins. The world. The devil. Anything that can harm you. Even death. He stands to fight for you and His weapons can't miss. In the Name of Jesus. Amen.
With might of ours can naught be done, Soon were our loss effected; But for us fights the valiant One, Whom God Himself elected. Ask ye, Who is this? Jesus Christ it is, Of Sabaoth Lord, And there's none other God; He holds the field forever. (A Might Fortress Is Our God, LSB 656:2)