John Lightfoot on John 3:5

[Except a man be born of water and of the Spirit.] He tells him, that the Jew himself cannot be admitted into the kingdom of the Messiah unless he first strip himself of his Judaism by baptism, and then put off his carnal and put on a spiritual state. That by water here is meant baptism, I make no doubt: nor do I much less question but our Saviour goes on from thence to the second article of the evangelical doctrine. And as he had taught that towards the participation of the benefits to be had by the Messiah, it is of little or of no value for a man to be born of the seed of Abraham, or to be originally an Israelite, unless he was also born from above.