Purpose is important. People may have many different motivations for doing the same thing. Saul, in his desperation to find someone to fight and kill the warrior Goliath, puts a price on the Philistine’s death. Israelite soldiers are encouraged to fight for the reward of money, a princess bride, and a tax exemption, but this is not enough to move anyone to fight against Goliath on behalf of Israel. Upon hearing Goliath taunting the Israelite army, David, however, is moved to fight. He is not motivated by the prospect of wealth, but is concerned about Israel’s reputation and God’s honor.
Why do we do the things that we do? Are we motivated by the things of the world, or the things of God? The things of the world are never the right reason to do God’s work. When we are motivated by the things of the world, we may in some ways be used by God, but we also risk being taken away from God, led to wherever the things of the world lead us. But when we are motivated by God and the things of God, we align ourselves with His purposes. We allow Him to use us for His work. And the work that God does is always successful. God will bring David victory against Goliath because David is for God. When we work on God’s behalf, moved by His purposes, we can also be assured of God’s victory.