How do we know that the new birth is essential for salvation?

The new birth is crucial to salvation, as Jesus declares in John 3:5 that one must be born of water and the Spirit to enter the kingdom of God. This assertion emphasizes the total change in character and disposition required for one to access eternal life. The doctrine of the new birth affirms that human beings, in their unrenewed state, possess a carnal mind that opposes God. Therefore, regeneration by the Spirit is not just beneficial but absolutely essential, as it transforms hatred into love and rebellion into submission to God's will and law.