What makes people feel they have to figure it all out? How can someone strengthen their spirituality through contemplation while avoiding a desire to try to understand everything?
Note: This answer was written before the OP was edited. A more direct answer is marked below, the following is build-up.
The Psalms are a great place to go for this. Psalm 143:5 says
A few verses down David implores God:
He's meditating on God's actions and word, but he's still asking God to teach him. He's marveling, wondering, thinking upon the truths of God's covenant with him and Israel, but he certainly doesn't have it figured out.
Additionally, the Bible talks numerous times of the mystery of God's nature and plan...
So don't worry! You don't have to figure it all out. It's quite mysterious and amazing, but, we can learn. After all, we've been given the entire Bible to study.
Also, we're going to be in heaven for eternity learning about God. If it takes an eternity to learn about God, don't worry that you don't understand it all right now.
How to stop trying to figure it all out
This borders on a pastoral concern, naturally, but I think we can take cues from the verses cited above. In my experience a good attitude is to
Why would you not want to figure it all out? Sure, you won't succeed. I don't suppose that you or I will completely understand life, the universe, and everything. Certainly not in this life, maybe or maybe not in eternity. (I'd guess no, but that's another subject.)
I want to be realistic in the sense that I'm not going to get frustrated when I fail to achieve an impossible goal. But if we don't set lofty goals, what will we strive for?
If we aim for the stars, we might at least reach the planets.