Your evangelical friend means well, but is confused: being “born again” refers to being baptized, not simply a personal conversion experience.
“Have you been born again?”
It’s a common question among evangelical Protestants, who often identify as “born again Christians.” The term comes from the third chapter of the Gospel of John:
Jesus says that to be saved, one must be “born again.” So making sure that one is “born again” is pretty important! But what, precisely, does this mean?
For most evangelicals, to be “born again” means only to have had a conversion experience in which one gives one’s life to Christ. That interpretation certainly goes far beyond what the verses actually say. Does Jesus give us any hint as to what he means by “born again”? Here are the next two verses:
In verse 5, Jesus clarifies what he meant by “born again,” saying a similar sentence again but substituting in the phrase “born of water and the Spirit.” While the term “born again” is vague enough to possibly mean simply a conversion experience, being “born of water and the Spirit” is obviously not, at least not exclusively – I’ve never seen anyone get wet from saying the sinner's prayer.
What Christian action involves water and the Holy Spirit? The answer: baptism. To be “born again” means to baptized. This is not only the current Catholic interpretation of this text (also held today by many Anglicans, Lutherans, and Orthodox), but also the interpretation given by the early Church Fathers – indeed all orthodox Christians prior to the 16th century Protestant Reformation.
For example, around A.D. 200 Tertullian wrote:
For the law of baptizing has been imposed, and the formula prescribed: Go, He says, teach the nations, baptizing them into the name of the Father, and of the Son, and of the Holy Spirit. The comparison with this law of that definition, unless a man have been reborn of water and Spirit, he shall not enter into the kingdom of the heavens, has tied faith to the necessity of baptism. (On Baptism, 13)
St. Gregory of Nyssa understood the verse similarly in the 4th century:
And a last example from St. Ambrose of Milan, also in the 4th century:
This has at least two implications:
First, this means that if you have been baptized, you can confidently say that you have been born again – and you should ask your born again evangelical friend if he or she has been baptized.
Second, if Jesus is talking about baptism and not simply a conversion experience – although any adult who is baptized must have put their faith in Christ – then Jesus is teaching something that evangelicals frequently deny, but that the Catholic Church has always maintained: that baptism is necessary for salvation.