What are the 'great things' God has done for His people?

In the sermon, great things mentioned include God's choice to make us His people, His deliverance of Israel from Egypt, and His continual support and protection. Most importantly, in Christ, He offers salvation to the lost, transforming them from a state of death in sin to life in Him. Reflecting on these great things, as seen in Mark 5, we understand not only past acts of salvation but also our present reality as those who have been given a new life, clothed in righteousness. It's vital for believers to recognize and celebrate these works of grace in their lives.