The following comes from Solid Joys, the daily devotional app from the ministry of John Piper. View online, or download the app on Google Play or iTunes.
* * * * * * * * * * * * * * *
I delight to do your will, O my God. (Psalm 40:8)
How does being born of God make the commandments of God a delight rather than a burden?
The apostle John says, “This is the victory that has overcome the world — our faith.” In other words, the way that being born of God overcomes the worldly burdensomeness of God’s commandments is by begetting faith. This is confirmed in verse 1, which says, literally, “Everyone who believes that Jesus is the Christ has been born of God.”
Faith is the evidence that we have been born of God. We do not make ourselves born again by deciding to believe. God makes us willing to believe by causing us to be born again. As Peter said in his first letter, God “caused us to be born again to a living hope” (1 Peter 1:3). Our living hope, or faith in future grace, is the work of God through new birth.
So when John says, “Everyone who has been born of God overcomes the world,” and then adds, “And this is the victory that has overcome the world — our faith,” I take him to mean that God enables us, by the new birth, to overcome the world — that is, to overcome our worldly disinclination to keep God’s commandments. The new birth does this by creating faith, which evidently includes a disposition to be pleased, rather than put off, by God’s commandments.
Therefore, it is faith that overcomes our inborn hostility to God and his will, and frees us to keep his commandments, and say with the psalmist, “I delight to do your will, O my God” (Psalm 40:8).