The Westminster Shorter Catechism
Q39 – What is the duty which God requireth of man?
A39 – The duty which God requireth of man, is obedience to his revealed will. (Mic. 6:8, 1 Sam. 15:22)
Q40 – What did God at first reveal to man for the rule of his obedience?
A40 – The rule which God at first revealed to man for his obedience, was the moral law. (Rom. 2:14–15, Rom. 10:5)
Q41 – Where is the moral law summarily comprehended?
A41 – The moral law is summarily comprehended in the ten commandments. (Deut. 10:4, Matt. 19:17)
Q42 – What is the sum of the ten commandments?
A42The sum of the ten commandments is, To love the Lord our God with all our heart, with all our soul, with all our strength, and with all our mind; and our neighbour as ourselves. (Matt. 22:37–40)