Great Question! I am hearing this question more and more as we have people participating in our community who are not "believers," and then find themselves strangely drawn to belief, but not yet knowing if they have moral or intellectual justification for believing in God. Part of the issue it seems is a view of "belief" itself and especially "how we believe." Let me explain.
There was a time not so long ago, and even still with us to varying degrees, when people believed that in order to know something they must take the posture of the"unencumbered self" and seek after universal truths independent of any particular communal narrative or influence. True "belief," it was asserted, is something we must attain to by ourselves, and is based on a blind optimism about the power of individualism and human reason to bring us to absolute certainty in knowledge. Religious faith, as such, was abstracted from the "text" of communal life, rituals and teaching -- the very context wherein faith was ordinarily born throughout human history!
More recently, there has been a philosophical shift back to an understanding of community as a basis for forming and believing universal truths. It would far exceed our present context to explain all of this philosophically. Suffice it to say that there has been a deep reevaluation in "epistemology" (a theory of how we know what we know) such as to make room for perhaps complementary epistemologies. One epistemology will emphasize the "unencumbered self" in search of truth based on a method of human autonomy and reason. Another epistemology will emphasize the "communal self" in search of truth based on a method of participation and human experience. I should say right off that I would not advocate an "either/or" approach to epistemology as if "reason" and "communal experience" are irreconcilable. Rather, there are some things we know by the study of propositional "texts", and there are other things we know by participation in communal "texts" or social narratives. For if we are inherently rational as human being, we are also at our core communal such that somethings can be known only by participating (communing) with them vs. by just thinking about them in a cold and detached manner.
Now to the present point, in so far as the knowledge of God is a communal kind of knowledge, it is a knowledge that we must discover by means of participation with God vs. merely thinking about God. As we will see, this is not to "check our brain" at the door of faith. Rather, it is to recognize that while faith in God is reasonable, it can't be attained by reason alone! This is exactly what we see, for instance, in the Old and New Testaments as pertaining to the significance of the "temple" wherein God is over and over again said to be present in the midst of the people in their communal gatherings, and it became the means by which people believed in God! [cf. the story of the early church in Act 2:1-47, note especially vs. 44-47, and then a more theological discourse about the relation of faith to participation in the life of God in, with, and through the "temple" of the New Testament church in Ephesians 2:1- 22.]
Anecdotally, this pattern of participating in the communal life of God in order to find faith in God is a familiar pattern here at CPC, even as it was in the early church. It assumes, again, that we know some things not merely by thinking about them in a cold and supposedly detached manner, but by participating or "communing" with them within the full range of our subjectivity. If there is a God, and if He has made himself known, the way of knowing Him will be by encountering Him where he may be found. According to the Bible and church history, God may be found in the context of the sacred communal narrative that is being played out in, with, and through His covenant community or "church." For instance, concerning the early church, one theologian describes the journey to faith this way:
Pagan converts to the [Christian] mainstream did not, for the most part, first understand the faith and then decide to become Christians; rather, the process was reversed: they first decided and then they understood. More precisely, they were first attracted by the Christian community and form of life... they submitted themselves to prolonged catechetical instruction in which they practiced new modes of behavior and learned the stories of Israel and their fulfillment in Christ. Only after they had acquired proficiency in the alien Christian language and form of life were they deemed able intelligently and responsibly to profess the faith, to be baptized.
George Lindbeck, The Nature of Doctrine, p. 132.
What an amazing observation! For isn't it an intriguing reversal of the way we tend to think-that the way to belief in God and the Christian faith is to first decide to believe and to participate in the life of God in, with, and through God's presence in the midst of his special community wherein that belief was more and more understood such as to eventually justify believing! If there is a God, and if He has made himself known, in so far as God is personal, wouldn't it make sense that He would expose himself not by some impersonal media, but within the warm and personal context of communal life?
And so the question has been raised, "how can I believe in God?" My answer is by "faith seeking understanding." By "faith" I mean that kind of knowledge that is gained by participating in it such as to then seek after the moral and intellectual justification in order to "believe" it (seeking understanding). Faith, like all communal knowledge, is a product of our will as much as our mind. We "will" to know God by participating with Him, even as the knowledge of God is found more and more reasonable on the basis of our experience and the reality of life as we know it with God.
Now at this point I anticipate a possible follow up question: Isn't it an expression of insincerity to first decide to believe such as to participate in the life of God vis-à-vis the church before actually "believing in God?" Fair question! This gets at the issue of what some have described as the "leap (or perhaps better leaps) of faith" toward coming to a settled conviction of faith.
So here is the thing, when it comes to this communal kind of knowledge, we are never in life really presented with a choice of "not believing anything." We are either acting in faith vis-à-vis participating with God, or we are acting in faith vis-à-vis not participating with God. There are two rooms connected by the door of faith-we either stand in one room or the other room as divided by this door of faith, but we don't stand in the door! To NOT participate with God in His community IS to act as if there is no God. To participate with God as described above IS to act as if there is a God. And so the reality is that in so far as you can't prove OR disprove God (by some kind of irrefutable method of modern science or rational foundation), you are left with no real option but to "leap" from the door into one or the other room. The basis for this leap is not anti-reason, but rather probability of reason lacking absolute certainty. It comes down to which way the scale tips, and then acting upon this in order to receive greater confirmation either way.
Finally, it can be observed that the scale of faith first tips based on all sorts of things. Perhaps you know someone who is a Christian and their way of life, their perspective, their response to suffering, their credibility as a person--whatever-- such as to intrigue you enough to tip the scale toward the possibility of belief in God, and you take the "leap" even if provisionally, and start participating with them in church. Perhaps you observe within yourself an emptiness or dissatisfaction with life enough so that you long for something that transcends life as to give it greater meaning and purpose--and you "leap" even if provisionally and visit a church. Perhaps you observe such beauty and order in the world, or such transcendent things as love, human worth, and future hope that you "leap" toward belief in God and participate with God in the church awaiting the confirmation of greater "faith" either way. Each "leap" presupposes that you suspend ultimate judgment, even as you act on a provisional judgment in order to discover "faith" one way or another.
Eventually, after a season of participating with God -- through learning the stories and teachings of the faith, through observing the rites and rituals of faith, and through experiencing the relationships of the community of faith -- the whole thing of belief in God is such as to make most sense of life as you know it and is most reasonable in terms of the answer to the ultimate questions of life, and you are able to say "I believe in God, and in Jesus Christ His Son for eternal life" and you are able to eat and drink of the sacred text of holy communion as someone who professes faith in Christ!