I determine right from wrong by considering two things that will provide the quality of wisdom that I cannot as a human cannot have:
The conclusion of the matter, everything having been heard, is: Fear the true God and keep his commandments, for this is the whole obligation of man. For the true God will judge every deed, including every hidden thing, as to whether it is good or bad.
He said to him: “‘You must love Jehovah your God with your whole heart and with your whole soul and with your whole mind.’ 8 This is the greatest and first commandment. The second, like it, is this: ‘You must love your neighbor as yourself.’
You may have guessed that these are quotations from the Bible.
Despite their assertions to the contrary, humans are influenced by a multitude of things in life that could make them do wrong, and even justify their wrongdoing. For instance, even though God says we shouldn't kill, humans have, and will, justify killing by saying that they came to them to teach them the gospel of Christ, or, some atheistic philosophy, and then upon their rejection, they kill them. Jesus never taught this, but it is their justification.
Greed, passion, jealousy, pride, ambition, pain, fear - I could go on and on, and all of these at one time or another will induce humans to do stupid, self-destructive, and ILLOGICAL things. Atheists say that their choices are completely based on reasoning and science and logic, but humans have a tendency to lie to themselves, too, and their choices too frequently turn out to be based on any one of these kinds of things.
On the other hand, atheism does not have an objective definition for morality.This is not to say that atheists have no morals. However, here is the difference:
An atheist can have morals or not have morals, but neither stance would deny their atheism. A person who, say, believes in the teachings of Jesus Christ, automatically knows that if they do wrong, it is displeasing to God, and since he or she loves God, that knowledge provides a strong incentive to change their course and do right. Indeed, the definition of what is right and wrong is imbedded in the teaching of Christ.
The "lists" of immoral behavior that many books take out of context are designed to malign God's sense of morality, by attributing human morality to God. All these lists are an unspoken confirmation that humans need the God of Justice, who alone is real, among all other gods. These lists demonstrate that immoral behavior comes from human imperfection, however, when the Bible records it, this does not mean that God approves of it.
People who truly accept the existence of a Creator also know that life is sacred, and a gift from someone who loves them. This would certainly give them incentive not to waste it, destroy it, or give it back.
For example, slavery as it was practiced in the US was entirely inhumane and immoral, and in history one can notice the infiltration of the division of different races of humans who are evaluated differently. In reality, there is only one race, the HUMAN race. Also social darwinism provided many heartless leaders with the pseudo-scientific justification for practicing some of the worst atrocities in human history.
On the other hand, it was people who espoused and lived Christian principles who took the lead in opposing these things, and it was they who established that all humans are deserving of their humanity, because they believed that all humans came from the same original pair.
Slavery as described in the Bible was not the same. It wasn't pleasant, but in most cases, such as for the ones who sold themselves into slavery, or in the case of war and devastation of their land, it was either that or starvation.
Acceptance of the existence of an absolute example - an intelligent, purposeful Creator, can move one to believe that all humans are brothers and sisters. Learning to love and respect such a Creator will add additional incentives to obey him. Acceptance of an absolute unimpeachable moral code, one which includes mercy and compassion, but which no one can influence with bribery or threats, can move one to believe that we are obligated to treat one another with love and respect.
But anti-theists who do murder are still anti-theists, and their position is not denied by their actions. However, Jesus said to those who say that those who call him Lord but do not do the will of the Father, that he does not know them, because they are workers of lawlessness.
Just to say, by loving and listening to our Creator, we have reason to repent and change, and really live a better life, now with a better hope.
Ecclesiastes 12:13, 14