If a person has grasped the meaning of God's grace in his heart, he will do justice. If he doesn't live justly, then he may say with his lips that he is grateful for God's grace, but in his heart he is far from him. If he doesn't care about the poor, it reveals that at best he doesn't understand the grace he has experienced, and at worst he has not really encountered the saving mercy of God. Grace should make you just.
Timothy KellerThe targets of this story are not wayward sinners but religious people who do everything the Bible requires. Jesus is pleading not so much with immoral outsiders as with moral insiders. H wants to show them their blindness, narrowness, and self righteousness, and how these things are destroying both their own souls and the lives of the people around them.
Timothy Keller