We can be content with simplicity because the deepest most satisfying delights God gives us through creation are free gifts from nature and from loving relationships with people. After your basic needs are met, accumulated money begins to diminish your capacity for these pleasures rather than increase them. Buying things contributes absolutely nothing to the heart's capacity for joy.
John PiperSin is what you do when your heart is not satisfied with God. No one sins out of duty. We sin because it holds out some promise of happiness. That promise enslaves us until we believe that God is more to be desired than life itself (Psalm 63:3). Which means that the power of sin's promise is broken by the power of God's.
John Piper