There is an age old custom to stay up all night on the night of Shavuos, the festival that commemorates receiving the Torah at Sinai. The basis for this practice is to rectify the fact that on the morning that G-d gave the Torah, the entire Jewish nation overslept. This is alluded to by a verse in Isaiah (50:2): "Why was there no man when I came? When I called, why was there none to answer?"
The question one has to ask is how in the world such a debacle could have occurred. The idea an entire nation could sleep late on the same morning seems strange enough, but that such a thing could happen on the morning that the Jews were to witness the very revelation of G-d. It's not as if they didn't know what was supposed to happen that morning. Indeed, ever since leaving Egypt forty-nine days prior, the Jews had literally been counting the days until their anticipated meeting with G-d at Sinai. The scenario strikes us as more than odd.
The answer is that the Jews slept on purpose.
Now, why would they go and do a thing like that? Had they assumed a nonchalant attitude toward the great revelation that was to occur that day? To the contrary: the Jews were very serious about receiving the Torah. They understood the magnitude of such an unprecedented event; and as such, they deliberately planned a mass "sleep-in" as the ultimate, culminating phase in their preparation for this most momentous occasion.
They knew that after forty-nine days of intense self-refinement, there was no more they could do to make themselves ready. A mortal being is only capable of so much. A human being can only reach so high. Unless of course, one could divest oneself of the trappings of the body and continue striving in a purely spiritual state. The Jews slept to achieve disembodiment. They slept so that their souls could leave behind the consciousness of physical existence and climb to the heights of heaven. This, they decided, was the final frontier in their preparation for communion with the Divine.
Of course, they fundamentally misunderstood that the giving of the very purpose of G-d's giving the Torah was to give us a means for sanctifying the physical and the mundane. G-d gave us mitzvos so we could make this world holy. Accordingly, the preparation for receiving the Torah should have also been connected with an attempt to imbue spirituality into the material world and not, as they assumed, to escape into a realm of the spirit.
In hindsight, it's easy to see that their plan was flawed. But how many of us often fall prey to this very same line of thinking in our own search for G-d? We spurn the world of the day-to-day in quest for what we deem to be more "lofty" concerns. Rather than trying to deal with regular life in a more G-dly manner, we run away from our real responsibilities and sanctimoniously indulge in a most insidious form of self-righteous, self-important escapism.