To be a better human and support the growth of human culture, or, for those who don't fear the idea of evolution or think that it's inherently in conflict with religious beliefs, to "evolve" and be supportive of the evolutionary process.
Recently, I watched a fascinating, excellently done Nova broadcast called Ape Genius, which tried to explain why apes, which are capable of using tools, creating primitive weapons for hunting small mammals, and even cooperating with each other as groups, do not have the same propensity towards developing societies that humans do. Given what we now know about what they are capable of, why aren't they hunting in packs, bringing down big game, and building primitive structures together?
The show is absolutely worthwhile and viewable online, for those of you who have missed it. The level of intelligence shown by the apes tested in the show is stunningly impressive... and yet, what they're missing that sets us apart makes all the difference.
Researchers have done extensive testing of various members of the ape family versus children at various stages of development, and have uncovered a few key factors to humans that apes don't posess.
Empathy / Mind-reading. Humans are exceptionally skilled at thinking about what's on other people's minds. A teacher, for example, needs to understand what a student knows and doesn't know. Researchers used to believe that chimpanzees lacked this talent entirely. Although recent experiments at the Max Planck Institute for Evolutionary Anthropology in Germany are showing that chimps share at least a bit of this skill, humans are clearly head and shoulders above the great apes in mind-reading savvy.
The Triangle. Watch a human parent building a block tower with a child and you'll see a special skill at work. Let's call it the Triangle; its three points are the adult, the youngster, and the tower. Both adult and child are not only focused on the same object, they know the other is focused on it too. The Triangle is the foundation for teaching—a mentor and pupil must jointly pay attention to the lesson at hand. Amazingly, humans seem to be the only great apes that possess this mental skill. (However, some other animals, such as dogs, also possess this skill, even if they're weaker in other evolutionary traits than apes.)
Impulse control. Whereas mind-reading and the Triangle are cognitive skills, the third mental talent that sets us apart from our kin is emotional. We seem to have much greater control over our emotions, and being less reactive and impulsive is a good way to get to the head of the class.
So, if these are the factors that set us apart and make us most human, it makes sense for us, as individuals, to see what we can do to "exercise" these most human of traits, whether you believe they are evolutionary advantages, or god-given. It's worth noting that the doctrines of virtually every religion emphasize several of these traits -- albeit not always in practice -- so it does clearly indicate ways in which people can reconcile spirituality with what it truely means to be a human in mutually beneficial ways.