Why is the doctrine of total depravity significant in Reformed theology?

Total depravity, a key doctrine in Reformed theology, teaches that every aspect of humanity—mind, will, and emotions—has been affected by sin. This condition means that individuals cannot choose God without divine intervention. As mentioned in Romans 3:10-12, 'There is none righteous, no, not one: There is none that understandeth, there is none that seeketh after God.' This doctrine lays the foundation for understanding why salvation must be entirely by grace, as it underscores the necessity of God's work in the heart of the sinner to bring about regeneration. In recognizing total depravity, believers appreciate the depth of God's grace in choosing and redeeming them despite their utter helplessness.