Christian responses to things like Alain de Botton's 10 Commandments - for Atheists usually focus on questioning the source of the morality. For example:
- Authority: Who says? Without a god, on what objective basis can you say people must be moral? Ultimately, the Atheist's authority is only their word.
- Motivation: Why bother? Theist's motivation is love for their lover, gratitude to a giver or fear of a punisher. Ultimately, the atheist's motivation is all selfgenerated.
- Power: Who can? The Christian will point to the Holy Spirit's enabling through Christ and the church. Ultimately the atheist can only rely on him/herself.
There is a lot of value to questioning atheist morality at its source, but you can also focus on the telos of atheist law.
Whether atheist or religious, law only ends up in two places:
- Guilt for failing to live up to the standard. Not just felt guilt (which not everyone may feel keenly), but real guilt.
- Suffering due to failing to live up to the standard. All moral failure hurts someone, or something in this world.
Jesus can be found in both those places. He lived out Alain de Botton's commandments, Moses' and yours - better than you could imagine. But he is also in the place of guilt and suffering. Before we get up in the morning and tie our moral bootstraps to walk out the door into the world he is in that place, bearing the weight of both guilt and suffering. He's there bringing an end to both the guilt and the suffering, and the law itself, for us.
One way I think this forward orientation may help in engaging atheist moralists is that it follows the direction of travel. Rather than going against the grain and pulling the atheist back to the source, it is accepting of the truth in atheist morality but goes with it to the end.