There are a number of meta-stories in the Hebrew Scriptures which shape how the people of Israel understood their relationship with God. (Let's not forget that this is the religious and cultural context into which Jesus was born and lived all of his life.) The story of the Exodus has echoes right throughout the Bible - it fundamentally asserts that God breaks into human history to side with those who are oppressed.
One of the many interesting details to this story is that it begins with the outcry of the Israelite slaves. The slaves don't cry out to their God, Yahweh, they just cry out in pain and suffering. Perhaps they feel that they have been abandoned and there's no longer any point in directing their pleas. However Walter Brueggeman, who is one of the leading Old Testament scholars in the world today, suggests that "all cries come up to Yahweh. Yahweh is a magnet for the voice of human pain. The narrative tells about the entry of God into the venue of rapacious economics." What a great phrase! It's an important reminder that God is deeply interested in economics and not just homiletics.
The story also has a missiological application: God responds to people who are suffering, regardless of whether they know God or not. God's priority is to rescue the people from their enslavement. It's not until they are free that they can consider the meaning of covenant.