Self-control is the ability to exercise restraint and mastery over one's desires and impulses, aligning one's actions with God's will. It is identified as a fruit of the Spirit, reflecting a life transformed by Christ. The bible compares a person without self-control to a city broken into and left without walls, illustrating the importance of discipline for spiritual strength and protection. Self-control empowers believers to live a righteous and purposeful life in obedience to God.