Sell the Sizzle, Not the Steak!
You will eat and you will be satisfied, and you shall bless. (Deut. 8:10)
The verse states "You will eat and you will be satisfied, and you shall bless." This is the commandment to recite Birchas Hamazon (Grace After Meals). The Talmud (1) notes that the verse contains an obligation to recite a blessing after eating. From where do we know that one is obligated to recite a blessing before eating? The Talmud had a premise to answer based on the following logic: If one is obligated to make a blessing after eating, certainly one must be obligated to make a blessing before eating. (See the Talmud there for the full reasoning.)
The Talmud asks further: we have a verse which tells us that one is obligated to recite a blessing before learning Torah. How do we know that one is obligated to recite a blessing after learning Torah? Here the Talmud suggests reasoning based on the opposite premise: If one is obligated to recite a blessing before learning Torah, then certainly after learning Torah one is obligated to recite a blessing.
The question arises: why is it more easily understood that one has to recite a blessing before eating than after eating, while for learning it is the opposite: it is more obvious that one recites a blessing after learning than before?!
In the physical world anticipation is a most powerful force, but the pleasure never lives up to the promise. Every pleasure is over-promised and under-delivered. The hype is always greater than what you actually get. One of the rules of marketing is: sell the sizzle, not the steak. Advertisers understand well that anticipated pleasure is far greater than actual pleasure. Just looking at the steak your mouth begins watering. However when you actually bite into it, it's just not the same. The sizzle is always better than the steak.
This principle helps resolve our question. If one is obligated to recite a blessing after eating when the actual pleasure has already passed (and was relatively disappointing compared to the anticipation), then surely before eating when the pleasure is great and there is so much excitement and anticipation you are obligated to recite a blessing. However, it is just the opposite in spirituality. Many times one has to push oneself to learn or to do an act of kindness; the pleasure beforehand is negligible. But afterwards, when one finishes learning or performing an act of kindness, the pleasure is just unbelievable. Therefore, if before learning when the pleasure is not that great one is obligated to recite a blessing, certainly afterwards when a person is in ecstasy, he is obligated to recite a blessing. In spirituality, the steak is always better than the sizzle!
1. Brachos 21a.