This passage is one of the Bible's big statements about the limitless character and power of God.  In it, the Apostle Paul gathers many fragments from the Psalms and from Isaiah 40:13.  These four verses are well worth using as a screensaver on your computer, printing them or translating them into your mother tongue and displaying them in your bedroom, kitchen or office.  Christians so easily forget the magnificent and awesome immensity of God.  Because of this, we limit our faith, which limits our prayers, which limits our actions, which shrivels our souls.

Paul uses different analogies to describe God's personality and activity.  A mining analogy - the riches of God are an inexhaustible seam of gold (Job 28:1-28); an academic analogy - God knows everything and how to apply that understanding to make everything work according to its design, even though we cannot understand it all (Ecclesiastes 8:16-17); a legal analogy - every verdict is 100% accurate, fair, just and righteous (Deuteronomy 32:4); an astrophysics analogy - the way He works is more complex than the mechanisms in the universe (Psalm 19:1-6).  Nobody can teach God anything (Job 38:1-11).  Nobody can claim that God owes them anything.  He is the reason behind everything, the means of everything and the destination of everything.  He is the focus point of glory for all eternity.

The wonder of the gospel is that we can know this God as a loving Father and Jesus as a faithful friend and Elder Brother (Hebrews 2:11), as we trust in Christ. The lying work of Satan is to make God seem small and make us seem big - in the same way that Eve was tempted (Genesis 3:1-5).  But the work of the Holy Spirit is to give us a big view of Jesus Christ and show us how great God is (John 14:26).
 
Alas, our view of ourselves and the world is often distorted because we see God distantly against the perspective of our own (supposed) greatness.  Instead, we need to see God in the way the Bible reveals Him to be, and ourselves in the light of His greatness. The truth is that the majestic glory of God engulfs everything; and yet although we are small, we are loved children, and grateful subjects in His kingdom.  In that perspective, our hopes and fears, our prayers and ministry will find their answer in His sovereign authority.