I wanted to believe for a long time (as in, I was drawn to mythology and fairy tales and researching religion, and felt it might satiate an urge inside) but grew up in an environment that glorified Science (ironically, Science became a god, in a way), and religion was pretty much ridiculed. Tbh, the Christianity taught at school didn't exactly make it enticing to become religious either.
Even as an adult, when I decided to explore religion more, I found it hard. Every time I moved in the direction of religion, my brain second-guessed me, as I was taught, and told me to stop being silly.
It wasn't until pretty recently, that I got why people can benefit from and actively seek religion - and how it's in no way incompatible with a science or critical thinking.
In essence, religion allows you to connect. Think of how much one can enjoy hanging out with of a good friend, family members at a great gathering, etc. It's the ambiance, the vibe, dare one even say...aura, which gets generated that we enjoy so.
Religion is a tool that allows you to do the same with the world, pretty much. All the people there, but - in my case as a pagan - also the plants, animals, the planet itself, even your own body and the cells that make it up. And of course, the dead ( and your ancestors), nature spirits, and all the other mythological creatures that people have told stories about for eons. Many of them were given form by the human brain trying to interpret that connection it feels through religion - often through a specific cultural/community lens. The same is true for God(s).
This gives you that feeling of being part of a tribe, called the Universe. It's the insight that we're all connected. You'll hear this as a favourite tune in just about any big religion to talk about in (insert sacred space). And it allows you to feel supported, embraced and filled with purpose. It's knowing you are never truly alone, and you are a part of something much larger than you could possibly fathom.
Many atheists/scholars I know feel the same way about the wonders of space, the universe etc, in a scientific way, ime. And in that respect, science and religion have more in common than their followers are often willing to admit. And are certainly compatible, when each side respects the other. Think of it as appreciating a tree for 'art' and the feeling it can inspire vs what a tree is,does and how it works. Now, connect with the tree for a holistic view of who this tree is and how it could inspire you with its personality, abilities, wisdom and life lessons (compare a birch vs an oak, for example), for a spiritual look at the same subject.
It is dismissing or pedestaling one of these over the others, and arguing against one by using the parameters of another that causes so much confusion and misunderstanding on this topic. All three are valuable ways of looking at the tree and learning from it.
When at it's best, this connection is what allows religion to inspire empathy beyond your kin and those you know, generosity, confidence - it gives one a steady footing and a place to belong. A family, of sorts. It inspires self-reflection, self-awareness and a sense of purpose - and as a result, a certain self-love, healthy pride and confidence. Which then positively affects those you influence in your life. And in that way, it can very much inspire personal growth as well as a sense of community that benefits everyone involved.
In short, it can bring out the best in people.
That said, religion is an imperfect tool to describe something that is hard to put into words but seems to be a shared experience for many people. Not everyone is equally adept at using it. And, of course, tools can be abused, manipulated and used to destroy all they are capable of creating.
Think
letter of the law vs
spirit of the law.
Edit:
I think that the best thing to compare it to as it is similar to that, is Love. It's abstract, nobody can prove it exists, science explains it as neuro chemicals firing in your brain, but it's inspired our entire species to become lyrical and prolific in an attempt to describe just how it makes us feel. It connects us to another like nothing else, and our existence just seems to come into focus with that special someone in our lives. And we are relentless in the pursuit of that connection
While Lust very much inspires the same kind of lyrical, passionate insanity, with much of the same brain chemicals in the mix, it is a very different beast. When someone who hasn't experienced love before asks someone who has what it is like, the answer almost invariably is 'you'll know it when you feel it.' - infuriating as that is.
But nobody really questions the validity of love, or its existence. Or for that matter, the questing for said love in your life. Or the usefulness/need for it in your life - despite all the heart ache, pain and misery it can cause. Or the abuse that happens in the name of Love.
Unlike the concept of Spirituality and God.
One can choose to remain celibate and unwed/unattached (and many who are devoted to God do so - one could wonder if that's because they find that the spiritual connection fulfils them enough that they don't need that material one?), but often they're viewed as 'missing out'.
Is the same true for those refusing to quest for a spiritual connection?
) X is a believer, 
