Gresham Machen in the 1920's and 1930's wrote about the issue of objectivity. It used to be that people were sure about objective reality and unsure of themselves. Now people begin to question objective reality and are sure of themselves.
I believe the same tendency Machen notes has continued and intensified. We should have great certainty in the truths of scripture and be doubtful of ourselves.
It is of course the teaching all through the bible of how our hearts are deceitful and trick us. We are very quick to excuse ourselves. That is why it is proper to have great certainty in the bible and a suspicion of ourselves.
Too often people have great faith in themselves and little faith in the bible. Where the bible seems not right they are quick to point out that the bible must be wrong on this issue because the bible seems to not make sense.
Of course the bible usually does not make sense because we do not like what it has to say. If you push people for why the bible does not make sense on moral issues usually you get a response something like: " It does not seem right or fair and who has the right to impose on my freedoms."
It is of course a difference of opinion. The sense of freedom is that no external power has the right to dictate upon our lives.
Of course the teaching of scripture is that the God of heaven and earth who created all things has such a right. As the Creator and sustainer of all things he has the right to declare right and wrong.
Of course to accept scripture's opinion we must first accept God. But the whole criticism of those outside the church that the bible's morality is deficient or the bible does not make sense is off track.
If you reject God than some of the bible's points on morality are easy to question, but if you accept God then it is folly to question his ideas. The bible is a completely consistent viewpoint on life and a highly rational one at that.
The skeptics who attack the bible often do themselves a disfavor of questioning the rationality of the bible. They of course wonder why the church has such a bad viewpoint of their arguments.
It is of course because their arguments are very poor because they have taken a grave shortcut and avoided the basis of Christian ethics. Their arguments only have power once you already agree about their presuppositions about God or often in their case the lack of a divine being.
You can only attack Christian ethics successfully once you get rid of the biblical view of God. Christian ethics are wholly consistent and rational once you accept that the God of the bible is who he says he is.