From the Gemara in Berakhot 4b:
The master said: “One should read Keri’at Shema and then pray [the Amida].” This supports Rabbi Yochanan, as Rabbi Yochanan said: “Who will merit the World to Come (Olam Ha-ba)? One who juxtaposes redemption [the blessing of Ga’al Yisra’el] with the evening prayer.”
My rebbe, R. Yitzchak Blau cites the interpretation of the students of Rabbeinu Yonah:
We link redemption and prayer because prayer, often referred to as avoda she-balev (service of the heart), exemplifies service of Hashem. This illustrates the fact that we do not view the exodus from Egypt as a self-sufficient act. No one can deny the joys of freedom, but the question remains what a person will accomplish with such freedom. Therefore, the Exodus from Egypt (Yetzi’at Mitzrayim) was only complete when the Jewish people accepted the Torah at Sinai (Matan Torah). We convey this point each day by following up our prayers about the Exodus with the quintessential avodat Hashem.
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Ultimately, freedom is not meaningful without a vision of how to live a noble existence. Jewish history is significant not because we became free, but because we accepted the divine laws of the Torah.
Freedom, though a noble political value seems slightly out of place in a religious context. In this vein, a professor of mine used to offer the analogy of an orchestra. If musicians in a symphony play whatever please, each according to his own rhythm, that may be freedom. But freedom, in this sense, isn’t the appropriate value for an orchestra, whose function is to create beautiful music. The players should be free but must use that freedom to obey the notes on the page.
Similarly, the Gemara teaches that the freedom granted to Israel in leaving Egypt is of a specific type. The beautiful music is created when that freedom is used to worship God.