A Christian must believe that.

Man is justified by faith in the atoning natural regeneration from above.

Romans 5:1

1 Therefore being justified by faith, we have peace with God through our Lord Jesus Chris

Matthew 1:21

21 And she shall bring forth a son, and thou shalt call his name JESUS: for he shall save his people from their sins.

Matthew 18:3

3 And said, Verily I say unto you, except ye be converted, and become as little children, ye shall not enter into the kingdom of heaven.

2 Corinthians 5:17

17 Therefore if any man is in Christ, he is a new creature: old things are passed away; behold all things are become new.

Ephesians 2:8-9

8 For by grace are ye saved through faith; and that not of yourselves: it is the gift of God: 9 Not of works, lest any man should boast.

Titus 3:5

5 Not by works of righteousness which we have done, but according to his mercy he saved us, by the washing of regeneration, and renewing of the Holy Ghost;