> The difference is, like Jesus taught, religious people will care for others expecting nothing in return (reward is from God)
But you admit that's not true. They expect something in return from God. I don't understand why this distinction even matters if the only thing that makes the reward worth it is just how 'immeasurably desirable' it is.
If atheists could get some similar reward (maybe their consciousness uploaded to a "heaven" simulation by a kindness-promoting nonprofit that feels effectively endless) depending on how kind they were to others during their lives, would they then be rational to be kind? Or would it still be chasing some sort of "reward" for their kindness?
Why does the reward originating from God matter?