Source of Virtue?

What is the source of virtue? When you see small children who are well-behaved do you assume that their parents are diligent and consistent in training them? In like manner do you make assumptions about the parents of ill-behaved children? Yet I declared a proverb to be invalid concerning the parents eating sour grapes and the effect it would have on the children, and went on to say that each person was responsible for their own virtue. Positive early influences are desirable, but I created a world in which each individual is accountable. My promise of redemption is the same for all, no matter how favorable or unfavorable their start in life.