How do we know that regeneration is a work of God?

The doctrine of regeneration asserts that a person cannot restore themselves to spiritual life. As seen in Ephesians 2:4-5, it is God who makes us alive with Christ, demonstrating that regeneration is entirely an act of divine grace. The Scriptures affirm that human efforts—even the most earnest ones—are insufficient for spiritual revival. C. H. Spurgeon clearly articulates that 'the new creation is as much and entirely the work of God as the old creation,' emphasizing God's sovereignty in salvation. Therefore, the assurance of regeneration lies in the acknowledgment of God’s power and mercy that revitalizes the spiritually dead.