The Kuzari explains why Hashem identifies Himself as the one Who took us out of Egypt, rather than as the Creator of the universe. The Exodus was a phenomenon that was clear for all to see. Hundred of thousands of Jews witnessed this unprecedented break with the course of natural events. While everyone was aware that there had been a creation, no man had been present. It, therefore, makes sense to refer to an event that would have greater credibility in the eyes of man.
Horav Yaakov Neiman, zl, offers an interesting response to this famous question. He claims that it simply is not necessary for the Torah to inform us that Hashem created the universe. After all, who else could have created it? Surely we did not create it! He cites the Chafetz Chaim who relates an analogy in the name of the Dubno Maggid. Two people were traveling together when one checked his wallet and discovered that his money was missing. Immediately, he grabbed hold of his companion and demanded that he return his money. “Why do you accuse me?” screamed the companion. “What proof do you have that I stole your money? Did you see me in the act of stealing?” The victim responded emphatically, “Why do I have to produce proof? Who else could it have been? Obviously I did not steal from myself. By default, it must have been you.”
The same concept applies to Brias Ha’Olam, the creation of the world. Man did not do it, so it makes sense that Hashem was the Creator of the world. When we are addressing the areas of human endeavor, we are making ourselves vulnerable to problems. We might forget about the “Hashem factor” in the miracles which we perceive. People often overlook Hashem, forgotting that it was He Who wrought the miracles, He Who brought about the healing, He Who saved us from disaster. It was necessary for Hashem to declare to Bnei Yisrael, “It was I Who took you out of Egypt,” in order to ensure that we do not err in believing that human intervention was responsible for Yetzias Mitzrayim.