Great is our Lord, and of great power: his understanding is infinite.
If there were a point where God stopped, then God wouldn’t be perfect. For instance, if God knew almost everything, but not quite everything, then God wouldn’t be perfect in knowledge. His understanding wouldn’t be infinite, as it says in Psalm 147:5.
Let us take all that can be known—past, present and future, spiritual, psychic and physical—everywhere throughout the universe. And let us say God knows all of it except one percent—He knows ninety-nine percent of all that can be known. I’d be embarrassed to go to heaven and look into the face of a God that didn’t know everything. He has to know it all or I can’t worship Him. I can’t worship that which is not perfect.
What about power? If God had all the power there is except a little bit, and if somebody else had a little bit of power hoarded that God couldn’t get to, then we couldn’t worship God. We couldn’t say that this God is of infinite power because He wouldn’t be of infinite power; He’d just be close to it. While He would be more powerful than any other being and perhaps even more powerful than all the beings in the universe lumped together, He still would have a defect, and therefore He couldn’t be God. Our God is perfect—perfect in knowledge and power. AOG006
Lord, how wonderful it is to know that I can worship a God who is perfect. I praise You for Your infinite understanding and power. Amen. 
147:5 his understanding is beyond measure. God is above and beyond human intelligence. There is no scale that can measure infinity.
147:4, 5 God’s knowledge of the stars suggests that He is more than equal to the problems of humankind. His power and understanding far surpass any other resource from which we may draw.
The two motifs of restoration and creation are sufficient to bring God’s people to worship. The psalmist exclaims how “great” (gādôl; cf. 48:1; 96:4; 145:3) is God’s royal sovereignty (“our Lord,” ʾadônênû) in “power” and wisdom (“understanding,” v. 5; see 136:5)! This conclusion relates primarily to his creative and sustaining powers over the universe (cf. Isa 40:26–28). By inference, God’s royal power and greatness extended to the world of creation are small in comparison to the depth of God’s love for his people (cf. Isa 40:26 with Isa 40:27–31). This brings the psalmist to a renewed consideration of God’s care for his own (v. 6).
 Tozer, A. W., & Eggert, R. (2015). Tozer on the almighty god: a 365-day devotional. Chicago, IL: Moody Publishers.
 Sproul, R. C. (Ed.). (2005). The Reformation Study Bible: English Standard Version (p. 866). Orlando, FL; Lake Mary, FL: Ligonier Ministries.
 The Open Bible: New King James Version. (1998). (electronic ed., Ps 147:4–5). Nashville: Thomas Nelson Publishers.
 VanGemeren, W. A. (2008). Psalms. In T. Longman III & D. E. Garland (Eds.), The Expositor’s Bible Commentary: Psalms (Revised Edition) (Vol. 5, p. 998). Grand Rapids, MI: Zondervan.