You often hear the term 'moral relativism' used pejoratively compared to the continued use of the morality of 2000 years ago.

What this needs is a new term - much like the use of the positive word gay instead of homosexual or pro-life instead of anti-abortion.

Moral relativism means is that your notion of morality changes over time - but like the arrow of time itself it always moves forward - moral relativism means moral progress, as compared with the static and eventually obsolete morality endorsed by all religions.

Quotes by Pope Ratzi:

"Having a clear faith, based on the creed of the church, is often labeled today as a fundamentalism. ... Whereas relativism, which is letting oneself be tossed and 'swept along by every wind of teaching,' looks like the only attitude acceptable to today's standards."

Indeed it is, and moral progress is better by definition.