I just had a long conversation with my brother, a devout Christian. With my help he has outlined the following argument why it might be good for me to follow Christian deontology:

1. Many of my moral values arose from my upbringing, as opposed to biology. This is evidenced by the fact that biologically similar people living in different places and epochs have different ideas of what's right.
2. Therefore many of my values originally came from the society that raised me.
3. Society's values were strongly influenced by Christian values, and many of our core moral prohibitions are inherited from Christian tradition.
4. The world is full of people who may want to edit my values ever-so-slightly while I'm not looking, in order to further their own agenda.
5. Also my values may drift, and most drift is harmful from the perspective of my current values.
6. A good recipe for countering this insidious deterioration of values is to consciously pull them back toward their original source, as long as it's something unchanging, like a book.
7. That means editing my values to more closely match Christianity. QED.

What do you think?