By Bridget Brenton, 101arguments.com
Guilt is almost universally experienced in this world. Children act guilty sometimes even before being told that something is wrong. Even dogs act guilty after disobeying their master. But why should disobedience cause a guilty response? It is almost as if we are in a world with a great Lawgiver with which we were all supposed to be in obedience to (and thus in perfect harmony with).
We all have a conscience. Why? 'Con' means with and 'science' originally meant knowledge. So conscience means 'with knowledge'. When we do something wrong it is with the knowledge that it is wrong. But without God there is no basis for anything being objectively right or wrong. Guilt takes place after, not before, doing something wrong, so it's unlikely that guilt evolved to "help us survive".
Some people have been influenced to accept different standards of right and wrong than God's standard but still hold to those values as if they were an objective reality. Guilt makes no sense in an arbitrary existence with no objective values, as in the model that evolution presents. I choose the model where guilt makes perfect sense, as I personally like to be able to make sense of the universe around us.
Guilt is a convincing argument for God because non-theists have to trivialize guilt as a hormonal or chemical imbalance, a merely irrational response. It is an unjustified cop out to call it illusory and yet it is exactly what we would expect if a holy God existed. If God has standards of holiness which we ought to reach but cannot, guilt would be the necessary product.
You really could not make that connection up. If God was real, guilt would exist to pull us up when we're going away from God's standards as a witness to our sinfulness and, therefore, guilt exists. It is not an afterthought to be explained away in ad hoc evolutionary stories, it is a witness to God that everyone has. The rare cases where people don't experience guilt are due to either brain damage or narcissistic personality disorder. The Bible talks about people who repeatedly do wrong having a "seared conscience" that is no longer sensitive to feeling guilt.
Guilt, very much like the majority of brain functions, cannot be accounted for by non-theists but those that believe in a holy God have an answer. Guilt is a very real response to our separation from that holy God who made us.