Morality derived from human nature (and thus from Darwin’s sociobiology) differs from divine law as expressed in the New Testament in significant ways. It is Aristotlean and Randian morality, is fundamentally selfish. Aristotle and Rand tells us to cultivate our own excellence. Darwin tells us we commit ourselves to conduct that will enable us to get along with others because humans are a social and political animal, we need to cooperate with others to achieve our goals.
Thus one should return good for good and evil for evil. Vengeance is not the Lord’s. He will not repay. One should do good for one’s kin, and forgive them their sins, and good for one’s friends, but not be nearly so forgiving of their sins. All men are not brothers. One should not harm other people without compelling and urgent reason, but the standard of what constitutes compelling and urgent reason is considerably greater for neighbors than it is for distant strangers. All men are not Hebrews.
It is a considerably more manly and muscular morality than that of Christianity. Transnational progressivism is Christian morality, Americans putting themselves on the cross for Muslims as Christ did, which is why we are losing in Afghanistan. Darwinian morality is classic Greek morality, Xenophon explaining that he had urgent need to slaughter, rape, loot and burn his way across Asia because the incorrigible bad conduct of the savages around him gave him no real alternative.
