This is Augustine’s understanding of grace(:) Grace is God’s giving us sovereign joy in God that triumphs over joy in sin. In other words, God works deep in the human heart to transform the springs of joy so that we love God more than sex or anything else. Loving God, in Augustine’s mind, is never reduced to deeds of obedience or acts of willpower. It is always a delighting in God, and in other things only for God’s sake. . . .

. . . Grace governs life by giving a supreme joy in the supremacy of God.

John Piper, The Legacy of Sovereign Joy