This is a question all of us are asked at one time or another by one of our Protestant friends. Sometimes it just comes up in conversations with Protestants. I underlined the words Bath and Rebirth because they mean born again or Baptism.
Regeneration is another word for the same thing.
The effect of Baptism is spiritual regeneration, which consists in the remission of every sin with the punishment due it, and the infusion of first grace. I can hear the wheels turning in your heads right now. Or perhaps, you have been fooled by them when they claim we are misinterpreting the verse. Let's go outside of Scripture and take a look at what the Early Church Fathers believed. The date in this case makes little difference.