The fear of the Lord is the beginning of wisdom.
Real satisfaction comes not in understanding God's motives, but in understanding His character, in trusting in His promises, and in leaning on Him and resting in Him as the Sovereign who knows what He is doing and does all things well.
One cannot declare that only his faith is correct and all other faiths are not. God is endlessly multi-dimensional so every religion that exists on earth represents some face, some side of God. One must not have any negative attitude to any religion but nonetheless the depth of understanding God and the depth of applying God's commandments is different in different religions.
Once He created the Big Bang... He could have envisioned it going in billions of directions as it evolved, including billions of life-forms and billions of kinds of intelligent beings. As a theologian, I would say that the proposed search for extraterrestrial intelligence (SETI) is also a search of knowing and understanding God through his works - especially those works that most reflect Him. Finding others than ourselves would mean knowing Him better.
Faith is a dynamic and ever-changing process, not some fixed body of truth that exists outside our world and our understanding. God's truth may be fixed and unchanging, but our comprehension of that truth will always be partial and flawed at best.
Understanding God's great love for undeserving people such as us, gives us insight into His great majesty. As beauty is in the eyes of the beholder, so great love reveals the nature of the One who loves deeply.
I firmly believe that the purpose of life is not this life. It is to equip us, whatever our role is going to be in the next life. And understanding God's story is really where I find the significance and purpose in my own story.
Understanding God is not attained by calling into session all arguments for and against Him, in order to debate whether He is a reality or a figment of the mind. God cannot be sensed as a second thought, as an explanation of the origin of the universe. He is either the first and the last, or just another concept.