I was asked recently if I thought there was anything good about religion. I felt it was an important enough question to give it a fair amount of thought. Coincidentally, I listened to a podcast that dealt with some of these issues. The podcast is called Unbelievable, and the particular episode is called Should atheists be more religious? Alain de Botton and James Orr. I like this podcast in general, because they pit the religious against the non-religious in an informal discussion for about an hour and a half. This particular episode raised the issue of religions' usefulness, and what can be borrowed by atheists.
One of the points was the contrast between the Christian view of humanity and the view of humanity as is often suggested by secularists. In the Christian view, humans are essentially fallen creatures, are naturally evil and need the grace of God to save them from this. The main secular view, which seemingly has been espoused since around the 1960s, asserts that people are naturally good and that culture is the dominant force which turns them bad, and further that through rational analysis one can overcome this cultural influence as science transcends all cultural barriers. This just doesn't gel with basic observations, I feel, and thus there is a benefit to the Christian view as a metaphor. If you've ever been to a daycare, it is quite obvious that children are naturally bad, or at least have more bad than good, and need to be saved from this.
Now, we don't need to believe in a magic garden and a talking snake, or assert that this observation of humanity has as a consequence that the Earth is 6000 years old, in order to draw value from it. In the same way that we draw value from Shakespeare, we can draw some value from the Genesis story (although I think there have to be better stories, which place women in a more favorable light!). Honestly, I think one can make a reasonable argument from evolution that reflects the ``fallen being'' idea. Essentially, we have a balance between selfish desires (clearly advantageous) and social desires (also advantageous, in social animals). A proper balance needs to be made, and there is a spectrum of selfish impulses, and the desire to suppress them in various ways. I think some of the rituals of religion help to remind us of this. Even gathering as a group on Sundays is an example of this - one is more likely to reflect on helping others when one is regularly together in a group.
It is true that there are things of benefit which, in the past, have only been the purview of religions. Getting together regularly, meditative rituals, ritual individual sacrifice (not human or animal sacrifice! think Lent here...), and traditions of giving (think Christmas) are examples of this sort of thing. Notice, however, that none of these requires the inclusion of superstitious claims, or claims about the cosmos or our role in it.
In addition to the benefits, there are a number of costs associated with these same examples that get dragged along with the religion. The blind following of authorities, the dogmatic adherence to invisible ``realities'', and the divisive nature of the practices are a few of these.
I believe that there are ways of getting the benefits with minimizing the costs. I also believe that the truth of claims is intricately related to their usefulness. What I mean is if you have a system of belief that does not reflect reality, then reality has a habit of making itself known, even if it might take a while. Finally, I think there is a lot to learn about what is beneficial to human mental well-being and societal well-being, and that some of these benefits currently are most clearly demonstrated in a religious context. I don't think that they need to be exclusively achieved in a religious context.