I've seen plenty of atheists online comment on how valuable the Sermon on the Mount is.
That's quite weird. How can they value it? Have they read the thing?
It starts with the Beatitudes:
- Blessed are the poor in spirit, for theirs is the kingdom of heaven. - but there is no Atheist heaven, only the earth.
- Blessed are those who mourn, for they will be comforted. - By whom? This is just a platitude then.
- Blessed are the meek, for they will inherit the earth. - How? By the strong giving up their power? Someone didn't read their Nietszche...
- Blessed are those who hunger and thirst for righteousness, for they will be filled. - By whom? Secular humanism with its relative morality? Haven't they heard of selfish genes and how we are all out for ourselves?
- Blessed are the merciful, for they will be shown mercy. - By whom?
- Blessed are the pure in heart, for they will see God. Blessed are the peacemakers, for they will be called children of God. - No God for you, though.
- Blessed are those who are persecuted because of righteousness, for theirs is the kingdom of heaven. - No Heaven again, just persecution down here, sorry.
- Blessed are you when people insult you, persecute you and falsely say all kinds of evil against you because of me. Rejoice and be glad, because great is your reward in heaven, for in the same way they persecuted the prophets who were before you. - Not really applicable to the Atheists, except perhaps as the opposite number.
Next is the Salt of the Earth and Light of the World, or the fulfillment of OT law - hardly applicable if the beatitudes aren't.
Then it is don't get angry at others and reconcile easily - okay, that's fine. But wait, then we prohibit looking at others in lust, divorce, oaths or explain how to fast or pray - doesn't sound much like how Atheists want to behave.
There is also loving your enemies and pacific turning the other cheek, here. That is a hard thing to do, which even Christians have a hard time with.
Jesus then says we shouldn't worry because God looks after us, and not to store up material possessions here, but in Heaven - um, our hypothetical Atheist only has the here and now, and no God, so...
Then we have not judging others, which is sound advice, and ending with a slew of bits about false teachers and building wisely on bedrock.
So...the vast majority of the Sermon on the Mount is inimical to the Atheist. It is just wrenching from context and freely cherry-picking to try and claim the mantle thereof. This amounts to saying I like the bit about not judging other people, a little spot of pacifism and maybe think the Beatitudes sound nice (though platitudes). Really not a logical coherent position.