Sefer Vayikra serves as the "central" book of the Chumash; on one side flanked by Breisheet and Shemot which detail the founding of, and raison d'etre of the Jewish people; and on the other side by Bamidbar and Devarim detailing the long and arduous struggle to reach the land of Israel. Smack in the middle is the smallest and I dare say the least 'interesting' of the books of the Chumash. Interestingly Sefer Vayikra takes place in a time vacuum. It is almost devoid of historical events and seems to interrupt the flow of the biblical narrative. Sefer Shemot ends on the first of Nissan in the second year counting from the exodus and Sefer Bamidbar picks up exactly one month later. (In actual fact Bamidbar begins just a week or so after Shemot ends - those events however were not recorded until the 9th chapter of Bamidbar - see Rashi on 9:1 as to an explanation why). Yet its loc ation indicates that it is sefer Vayikra that is the focal point of the Torah. It contains, as Rashi points out "the majority of the essence of the Torah" (see 19:2).
Interestingly and perhaps surprising to many it contains the greatest number of mitzvoth (247 according to the classic count of the Sefer Hachinuch ) - mitzvoth being the essence of Torah. Traditionally Jewish children began their learning of Chumash not, as is common today, with sefer Breisheet but with Vayikra. Yet this book more than any other seems the least relevant to us today and certainly not one which might excite children. Only when we reach parshat Kedoshim with its powerful and uplifting charge to holiness does Vayikra become a living text for many.
Nonetheless the korbanot play a major role in defining the essence of Judaism, regardless of whether or not sacrifices are actually brought. A quick (and incomplete) perusal of the nature of korbanot will illustrate the point. Korbanot which appear to be very very ritualistic in fact emphasize Judaism's rejection of empty ritual. As our prophets repeatedly tell us G- d does not really want our sacrifices per say, rather He desires the character traits that come with striving to come close to G-d. This requires sincerity - even an improper thought can disqualify a sacrifice. It is from the laws of sacrifices that the Talmud derives the principle of mitzva haba b'Averiah - a mitzvah made possible through the commission of sin which renders the mitzva worthless and worse. Closeness to G-d can never come at the expense of our relationship to man. Furthermore non Jews were allowed to offer korbanot; our Torah has a universal message for al l of mankind and seeks to bring all people, regardless of their actual religion, close to G-d.
The general laws of Korbanot even connect us to Pesach. "Do not make any meal offering that is sacrificed to G-d out of leavened dough ( sh'or ) because you may not burn anything fermented or sweet as a fire offering to G-d" (2:11). What is wrong with a little chametz with our sacrifices? The Sefer Hachinuch explains that the obligation to ensure all our meal offerings are matza symbolize that we must worship G-d with alacrity as any delay will cause fermentation. We must move quickly and with zeal in worshipping G-d. Remaining static causes stagnation and waste. Matza can remain indefinitely but let the yeast rise and within a couple of days it is no longer fit for consumption. Furthermore matza symbolizes our humility - the defining trait of Moshe Rabbeinu. Matza represents slavery. It is the ideal food to serve a slave - easy to make, cheap, filling and does not spoil. It is also the food we ate as we became free symbolizing our replacement of human bondage with servitude to G-d, which is the highest form of freedom that one can attain.
The bringing of korbanot, for the ancient world at least, was the most natural way of expressing one's desire to connect to G-d. As history unfolded the consumption of meat was no longer associated with service to G-d but rather became just a part of our diet. Bread became our staple food of man replacing the meal offering to G-d. With this understandable transformation much of the underlying values embodied on the korbanot were easily forgotten.
Pesach is so rich in meaning for modern man serving as a focal point for Jewish identity and observance for so many. The pesach seder today is actually a pale imitation of the original seder which focused on the korban pesach , the sacrifice of the paschal lamb. Yet that has not stopped it from becoming such a powerful tool for the teaching and practice of Judaism. It should be no different all year long. While we no longer have korbanot our tables can and must be altars on which we serve G-d giving us a daily opportunity to offer ourselves to G-d as we strive to come closer to Him. Shabbat Shalom!