The Psalmist said: "The earth is the Lord's and the fullness thereof" (Pg. 24:1). Taking this statement literally, and deeming it appropriate to acknowledge the fruits of the earth as a gift from the Lord, the rabbis instituted the practice of reciting a benediction when partaking of any of them.
Hence, Judaism prescribes blessings to be said before and after eating, as well as before enjoying fragrant aromas, or upon seeing pleasing and awe-inspiring sights. In this way, the satisfaction of a physical craving is raised into the realm of the spirit. Eating becomes a religious act (Hertz, Daily Prayer Book, p. 961).
Rabbi Abraham Isaac Kook elaborates this concept, explaining that physical enjoyment fulfills its purpose only if it serves at the same time as I vehicle for moral satisfaction, i.e., the acknowledgment of God in the world. A person who partakes of things without saying a blessing first, and uses them only for the satisfaction of physical needs, reduces the value of the thing enjoyed by not fulfilling its higher purpose in the world (Kook, 'Olat Re'iyah, 1:345).
He further stresses that holiness rests in man's seeking moral fulfillment even in physical pleasures. When man acknowledges God with a benediction, and thus recognizes God's creation in whatever he enjoys, he will experience a heightened appreciation of God's grace, lovingkindness, and wisdom which are present in all creation (ibid., p. 347).