What is sin? It is the glory of God not honored. The holiness of God not reverenced. The greatness of God not admired. The power of God not praised. The truth of God not sought. The wisdom of God not esteemed. The beauty of God not treasured. The goodness of God not savored. The faithfulness of God not trusted. The commandments of God not obeyed. The justice of God not respected. The wrath of God not feared. The grace of God not cherished. The presence of God not prized. The person of God not loved. That is sin. John Piper