The Heidelberg Catechism: Lord's Day 2
3.Question: From where do you know your sins and misery?
Answer: From the law of God.
 Rom. 3: 20;
4. Question: What does God's law require of us?
Answer: Christ teaches us this in a summary in Matthew 22: You shall love the LORD your God with all your heart, and with all your soul, and with all your mind. This is the great and first commandment. And a second is like it, You shall love your neighbor as yourself. On these two commandments depend all the law and the prophets.
 Deut. 6:5.  Lev. 19:18.
5. Question: Can you keep all this perfectly?
Answer: No, I am inclined by nature to hate God and my neighbor.
 Rom. 3:10, 23; I John 1:8, 10.  Gen. 6:5; 8:21; Jer. 17:9; Rom. 7:23; 8:7; Eph. 2:3; Tit. 3:3.
What Must I Know? A sermon by Adrian Dieleman
The Heidelberg Catechism
Lord's Day 1