Half of the uses of the word "redeemer" in the Bible are found in the book of Isaiah, with lots of other variants of this word like redeem and redemption scattered throughout the Bible. Isaiah clearly wants us to see that God is the redeemer of Israel and as seen through the rest of Scripture, he is also our redeemer.
God is shown to redeem his people from the oppression of Babylon (earthly powers) and spiritual apathy and idolatry (spiritual powers). The Evangelical Dictionary of Theology defines redemption as "the means by which salvation is achieved, namely, by the payment of a ransom." God is pictured again and again as the one who brings this about on behalf of his people.
God redeems his people from Egypt, Babylon and other earthly powers and especially frees his people from the dominion, reign, and power of sin. He frees us from being slaves to sin and releases us to live for him.
The description of the sins of Israel are very stark in Isaiah 43-45. They have stopped talking to God, stopped worshipping him and have replaced God with gods made by their own hands. Despite this behavior, God still is seeking to woo his people back to him. He is a redeemer and thus no matter how far we may drift from him, he still remains the only means of salvation, the only means of life and the only place for true fulfillment in the universe.
Question of the day: Why does God continue to pursue his people even when they resist him?
God my Father, thank you that you are my redeemer. Thank you that through the life, death, and resurrection of Jesus you have secured salvation for me. Help me to remember the staggering cost of my salvation and respond with gratitude, worship, and service for all that you have accomplished for me. Amen.