Theological themes of the book of Exodus (from the Literary Study Bible):

• The sovereignty of God: God rules all nations, working in history to reveal his glory.
• Revelation: God reveals his will and character in what he says and what he does, so that his people can known him as their God.
• Salvation: God releases his people from captivity, redeems them from slavery, and adopts them as children.
• Covenant: Israel is rescued because God remembers his covenant and restored because God renews his covenant--his everlasting love commitment to his people, sealed in blood
• Law: God's law is both a gracious gift for the people he has redeemed and a perfect standard for human behavior.
• Holiness: God has set his people apart for holy service, and everything associated with his worship is to be kept perfectly sacred.
• Judgment: God justly executes his wrath against his enemies.
• Atonement: Through the various offerings made at the Passover, on Mount Sinai, and in the tabernacle, Exodus shows that God forgives sin only through a righteous sacrifice of blood offered in the place of sinners. 
• Worship: the goal of life is to glorify God, who has the right to tell us exactly how he wants to be served and worshiped.