Who hath measured the waters in the hollow of his hand, and meted out heaven with the span, and comprehended the dust of the earth in a measure, and weighed the mountains in scales, and the hills in a balance?
Imagine going out millions of light years into space and finding a body so vast that you could throw all our solar system into it. Like throwing a shovelful of coal into a furnace, it would simply swallow up our solar system and go on. After you’ve thought of all that, remember that God contains all that. Remember that God is outside of all things and inside of all things and around all things. Remember that our God made it. That is the immensity of God….
We have here in Isaiah that which is vaster and more awesome than anything that ever came out of the mind of Shakespeare. It is the thought of the great God … moving through His universe … with its worlds so big that our whole solar system would look like a grain of sand by comparison. And God stands out yonder and calls all of these millions of worlds as His sheep; He calls them all by name and leads them out across the vast sky.
I’d say this is the highest thought I know of, in the Bible or out. And God does this “by the greatness of his might, for that he is strong in power; not one faileth” ([Isaiah] 40:26). AOG023, 025
Lord, You are more immense than I can imagine, yet You are a personal God who knows me by name. I bow before You in awe. Amen. 
40:12 Who has measured … in a balance …? God alone has power to create the physical universe and the earth in perfect balance, weighing mountains and seas perfectly, so that the earth moves perfectly in space. This matter of the amazing balance of our planet is called the science of isostasy.
40:12 Who has measured the waters in the hollow of his hand and marked off the heavens with a span, comprehended the dust of the earth in a third of a measure and weighed out the mountains in the scales, and the hills in a balance? Creation imagery affirms Yahweh’s sovereignty; He is the only Creator. These questions, which reflect Job 38, are designed to illustrate the finite nature of the created world compared to the infinite God who created it.
the hollow of his hand An image of the sheer immensity of God in His power over the universe. The imagery of God holding the oceans in the hollow of His hand and covering the heavens with the width of His hand sets up the later contrast with humanity—where the nations are little more than a drop of water or a speck of dust (see Isa 40:15 and note).
 Tozer, A. W., & Eggert, R. (2015). Tozer on the almighty god: a 365-day devotional. Chicago, IL: Moody Publishers.
 MacArthur, J. F., Jr. (2006). The MacArthur study Bible: New American Standard Bible. (Is 40:12). Nashville, TN: Thomas Nelson Publishers.
 Barry, J. D., Mangum, D., Brown, D. R., Heiser, M. S., Custis, M., Ritzema, E., … Bomar, D. (2012, 2016). Faithlife Study Bible (Is 40:12). Bellingham, WA: Lexham Press.