Great is our Master and His greatness is beyond investigation (Tehillim 145:3), where our minds cannot reach. The author of Sefer Chareidim writes that just as a young child who only knows how to count to ten, if he were told that something is beyond measure or count, he would picture a hundred as being “beyond measure or count.” Later, when he learns to count to a hundred, then a thousand or ten-thousand is “beyond count” etc. And that is how it is with us; no matter how much we can imagine about the greatness of our Master, we can fathom no more than a little child who does not know how to count higher than ten.
Nevertheless, it is proper that whenever we can we should remember the greatness of our Master to the best of our own limited ability by looking at the vastness of our humble world, and how this world is but nothing compared to the universe above it, than compare that to the world above that and the world above that… millions of ever greater realms “beyond measure or count.” And all of that is nothing relative to the greatness of our Master. We must believe with perfect faith that our minds cannot fathom even a millionth of His greatness. This thought coupled with thinking about the opposite — the lowliness of Man the multitude of favors and love of the Creator towards the person — should arouse love, awe, humility, and joy in His presence. This is the root of all of Judaism and pure fear of God. Fortunate is the person who regularly thinks about this as it becomes a mitzvah that leads to another and another…. It is a protection against sin and guarantees that the person’s service to Hashem is whole.
This was the practice of the early pious ones, they would tarry for one hour before each prayer (see Berachos 30b) in order to contemplate the greatness of the Creator and the lowliness of Man, then they would stand up to pray as a flea given the opportunity to serve the exalted, elevated, fearful and awesome King. This is a great principle in Torah and this is all there is to Man.

