Caliber (beware of my run on sentences, I am at work. )
This lies close to my heart. I am agnostic, but I find the longer I am out of the borg and deal with my anger towards the leadership of JW's, the less antangonistic I am of theistic beliefs, if only for the utility it offers individuals, not for how it causes problematic group think solutions. (i.e. organized religion)
I don't totally agree with those who say all faith is ignorant. I would equivocate on that by saying that for anyone to really promote the worship of a deity in absolute faith with only ancient scrolls and no other evidence certainly open themselves up for rightful criticism. For better or worse (I would say for better) leaving a cult like JW's causes one to investigate all that comes to them. That includes all religious theology and their source material, especially their holy books. This is healthy, and all should do it, even if all can't.
A problem with trying to find a purpose in life through religion is that to say "Eureka, I've found it" is to put on blinders as to all other forms of worship and views of spirituality. Just because someone gets a certain feeling and a purpose in life which may benefit them doesn't allow for them to offer their own personal solution as one for all! We all have to allow for other solutions, and that individuals will find purpose and meaning in their own way.
Here is where it gets tricky, because according to the Christian source material, the NT, Jesus does say to preach and advocate all to believe on him and his human sacrifice. Ok. I accept that Christians who take the bible literally are going to follow this. I used to myself in the way I was raised to understand such passages. Regretably, the evidence over 2000 years does not support a group think approach to Christianity.
Yet, so many get a purpose in life by following Jesus! Why would I take that away from them.
On the other hand, why would a Christian assume, when I inform them I don't worship Jesus, that I need him, and my eternal soul is at risk? It's at that point that an agnostic or an athiest will defend himself by going after what they often know so well: The source material (OT and NT of the bible) is not what some of its promoters claim it to be.
A belief or a philosophy that truly gives purpose and meaning must come from within, from some sort of realization. I am not implying supernatural, mystical dogma. It is my strong belief that these decisions are made on ligher evidence and lighter thought then perhaps is called for. Those with a real calling in life often mine deep in themselves to stay true to their calling. If you can't explain why you believe one way or the other, and you can't be intellectually honest enough to acknowledge the limitations of your belief system, then you need to dig deeper I think.
Theism or Atheism is not a requirement either way to have a purposeful, meaningful life.
Faith, hope and love are all necesarry, and Paul wasn't the first ancient to note this as a positive aspect of being human. Let me break those 3 down this way
We must have faith that tomorrow will be better then today. How we get to that point is personal. Atheists do have a lot of faith, just not in god.
Hope, which is closely associated to faith, is best summed up by those who hope in, for example, Obama, that he will be an excellent president. There are legitimate reasons for this hope. Where one chooses to invest their hope is also a personal matter, but Atheists are among the most hopeful people I know. Why? Because (this is an anecdotal generalization) they also tend to be humanists, and believe in man, despite the evidence that bad people will seek to exploit and harm when they can. They also take the evidence of good that mankind can do and make that their own.
Love: If we don't start with a healthy love and respect of ourselves, then we cannot love another person. A theist I might add, without proper self love, cannot love god the way they would wish to. If one depends on religion or another person to have any self esteem and loveof self, they often set themselves up for disappointment.
Once you own yourself, who you are, and love yourself, then you can have faith in others, a hope for the future, and can really unconditionally love others from your heart. This is something that theists and atheists can do, even if they never agree on religion or god.
These are rambling thoughts I know. I am still working out my purpose in life, even as I write this, even though I know what the evidence says about god and the bible. I can't ever go back there again. But I can strive to be an ethical, spiritually open minded person. That isn't the sole provence of theists.