Mercy even with us is an optional virtue; we do not have to be merciful. We usually admire people who are, but we do not say that people must be so. We say everybody must be just. We say, for example, an employer, if he agrees to pay a certain wage, must pay that particular wage. If he does not pay it, then he is unjust and is liable to a lawsuit. All our contracts are based on the integrity and honesty and justice of people with whom we do business. They are actually subject to trials and imprisonment and even execution if they violate their duty of man to man. What about mercy among men? We love it. We admire it. We encourage it. We sometimes practice it. But we do not say mercy is obligatory… If this is true even of human affairs, we can see immediately that God does not have to be merciful. He gave us life and conscience. He gave us intelligence to meet our obligations, and He has a right to hold us responsible for using them. He has no further obligation to forgive us if we do not. We say that the Judge of all the earth cannot do wrong, but we cannot say that the Judge of all the earth must be merciful.