How do we know that being born again is necessary for salvation?

In John 3:5, Jesus emphasizes that one must be born of water and the Spirit to enter the kingdom of God. This necessity reflects the truth that human beings are spiritually dead in their sins and incapable of understanding or accepting God on their own. The new birth, a work of the Holy Spirit, is essential as it is through this divine transformation that a person can have true faith and repentance, which are the fruits of the new life given by God. Romans 8:7 also notes that the mind set on the flesh cannot please God, reiterating the need for a spiritual awakening.