If we must not act save on certainty, we ought not to act on religion, for it is not certain. But how many things we do on an uncertainty, sea voyages, battles! --Blaise Pascal
When I was younger, I needed lots of certainty about things in life. All questions required answers. But as I have grown older, I am not as certain about some things as I used to be. I see life as more complex now than it was twenty years ago. People are more complicated than it seemed when I was younger. Some answers that appeared to suffice for questions I had years ago are no longer adequate; and now, for many of those questions, I am okay with the mystery. And some questions I had when I was younger no longer matter. The questions I have now seem larger, more significant, and therefore more difficult to answer.
I don't want to be misunderstood. I still have plenty of deep convictions that I embrace in my life and faith. I am not a fideist, which I find to be an irrational position. My Christian faith is indeed faith, but I am also a Christian because I am persuaded that it is reasonable, that it best makes sense of our existence. It's just that I have come to see that not all questions of life and faith are created equal. Moreover, not all answers are equal either. Whether or not Jesus has been bodily raised from the dead is a question that is indispensable to the truth of Christianity in a way that the historicity of Jonah is not. That does not mean that the resurrection of Jesus can be "proven," but it can be demonstrated as a reasonable position to take.
It seems to me that essential to a mature spirituality is sifting through the questions of life and realizing that the certainty we require with so many questions not only cannot be had this side of perfection, but it is not critical that they be answered completely. It is okay to live with ambiguity. That does not mean that we don't ask the questions and search for explanations that seem reasonable. The quest for truth is a noble one; but it is an endeavor that will always be provisional, will by necessity be incomplete this side of eternity. Even Jesus Christ, who is the Truth (John 14:6), does not reveal God exhaustively, though he does reveal God uniquely and decisively.
St. Paul reminds us that "we know only in part" (1 Corinthians 13:9a). He wrote this in the same letter in which he also said, "if Christ has not been raised, then our proclamation has been in vain and your faith has been in vain" (15:14).
Ambiguity is okay... it doesn't destroy the quest for truth, but it helps us to prioritize what questions are truly important.