The Book of Vayikra opens with a peculiar turn of phrase: "And (He) called out to Moshe, and God spoke to him. " Apparently, as readers, we were unaware that the Book of Shmot came to an abrupt end, in mid- sentence. For that matter, we are not necessarily aware that we are reading the continuation of the story as we begin the Book of Vayikra. Only when we consider the Book of Vayikra as the continuation of Shmot and read them contiguously do we begin to grasp the connection.
To be sure, God calling out to man - especially to Moshe - is not an unusual occurrence in the Torah; nonetheless, the opening verse of Vayikra is different. Now, God calls out from within the completed Temple. To fully understand this difference we need context. Reading Vayikra in the context of the final verses of Shmot helps us to understand that Vayikra is not merely the continuation of the Book of Exodus - it is the culmination of the Exodus itself. A metaphor found in the book of Jeremiah helps us gain greater insight into the story:
"Go and proclaim in the ears of Jerusalem, saying, 'Thus says God: I remember the kindness of your youth, your love as a bride, how you followed Me in the wilderness, in a land that was not sown." (Jeremiah 2:2)
God reminisces fondly about the early days of His relationship with the Jewish People: In Egypt, the Jews were like a damsel in distress, liberated by a "knight in shining armor." After He rescues them, they follow their savior off into the desert "like a love-sick bride," to their rendezvous at Sinai.
Standing at Sinai, vows are exchanged, and Moshe goes up to bring down the tablets of stone, a symbol of their unique and exclusive relationship (analogous to a wedding ring), to complete the marriage ceremony. At that precise moment, havoc is unleashed. The erstwhile lovesick bride gets cold feet; she backs away from her commitment and indulges in a fling, seeking thrills with a cheap imitation of her betrothed. At this point, talk of marriage seems absurd; the possibility of a life together seems to have vanished into thin air. Nonetheless Moshe intercedes, and soon the relationship is back on track. There is regret, repentance, and the relationship is repaired. Moshe ascends the mountain once again, and brings a second ring. They build a home, a place in which their love can be expressed, experienced and nurtured.
The Book of Shmot comes to a close as the building is completed. The structure stands, ready to embody and facilitate their unique relationship. Only one thing is missing: intimacy. And that is what the Book of Vayikra is about: intimacy with God, which may also be called "holiness". Certainly God has spoken to Moshe many times; Moshe even went up Mount Sinai and met with God at the summit. But this is different; now, man has made place for God down on earth. There is now an aspect of permanence to this relationship. A home has been built for them to share. Up to this point, the romance has been beautiful and uplifting: It is certainly an exalted gesture for man to lift himself toward the heavens and try to connect to the holiness above, but it is quite another matter to bring the holiness to this world. This new stage of the relationship requires constancy, commitment of a totally different order. For their relationship to fully blossom, they must shift from the sensation of being swept away by a love affair, and begin to nurture and maintain that love in a constant, ongoing and stable relationship of commitment and attentiveness.
This is what the Book of Vayikra is about, and it is the message of the very first verse. While the previous book ended with a completed house for God, Vayikra begins as the voice of God calls out to Moshe from inside the house. Holiness has been successfully brought down to earth; now, the world "below" has a chance to be elevated. Now the bride and groom can start their life together, in the home they have built for their shared future. Now, intimacy begins.
For a more in-depth analysis see: http://arikahn.blogspot.co.il/2014/03/audio-and-essays-parashat-vayikra.html