But we must also make a little effort to receive this biggest of gifts. Through natural means alone, we can never overcome our yetzer hara, and we would become discouraged and stop even trying to fight. The ox represents the elevated part in each of us, our gazing heavenward, our desire to attain lofty spiritual goals. The donkey, on the other hand, is symbolic of everything physical, materialistic, and earth-bound. If we want to serve Hashem, to plow and labor in the field of spiritual elevation, we cannot hope to succeed if we are still yoked to the donkey within.
Every prayer makes an impact in the higher spiritual realms.
When a prayer seems to have fallen by the way, we look at it as worthless, and yet it makes an awesome impact on the very fabric of reality. Far beyond our comprehension in the loftier spheres, that little prayer is moving worlds. Heaven is the abode of angels, so it would seem more logical for the angels in Yaakov's prophetic dream to first descend and then ascend. This led our Sages to conclude that there were two sets of angels - those who had hitherto escorted Yaakov while he was in Eretz Yisrael , and those who were to become his escorts when he left the land on his way to the home of his uncle, Lavan. The Eretz Yisrael angels don't leave the Holy Land, so they went up the ladder back to Heaven, while the angels in charge of escorting outside of Eretz Yisrael came down to take over this responsibility.