Blondie while researching that scripture on the Pharisees traversing land and sea to locate a disciple that would become so bad, Jesus said they would merit "double the judgement of Gehenna or Hell" I came across different renderings of this verse.
These Jewish Proselytes were not infants or children, coming on age in Ancient Israel was 30 years old(There were a few Pedophiles that tried to claim "our sexual abuse done while in our late teens and twenties should not count because we were not of age!" Here's something new I learned while trying to better grasp False Prophets and Wicked People making people worse.
JWs used age 30 as the age of adult hood and responsibility and they want 7 to 16 year old kids to give their life to the Watchtower Organization, they truly don't know their own faith! Do they think everyone who came down to see John-the-Baptist and got baptized were kids, they were all adults who knew they needed to show a change in heart or some type of repentance(Luke1-2). JWs don't know their faith because the Watchtower does not teach them the Bible or historical religion out of fear they might leave.
Gills Bible Commentary
"Ethiopic version reads the words, "baptize one proselyte, and when he is baptized"; referring to a custom among the Jews, who baptized; or dipped their proselytes in water, as well as circumcised them; about which there are great disputes in their writings; some alleging, that the dipping of them was necessary to the making them proselytes; others affirming, that it was not:
"a proselyte that is circumcised, and not dipped, dipped, and not circumcised, the whole follows after, or depends on circumcision, says R. Eliezer.''
R. Joshua says, even dipping delays it; (i.e. the want of it, hinders a man from being a proselyte;) but R. Joshua ben Levi says, it should go according to the tradition of Bar Kaphra; for the tradition of Bar Kaphra is,
"that he that is circumcised, and not dipped, lo! he is right; for there is no proselyte but what is dipped, because of the pollutions that happen to him (e).''
And elsewhere (f) this is debated in the following manner:
"a proselyte that is circumcised, and not dipped, R. Eliezer says, lo! this is a proselyte; for so we find concerning our fathers, that they were circumcised, but not dipped. One that is dipped, and not circumcised, R. Joshua says, lo! this is a proselyte; for so we find concerning our mothers, that they were dipped, but not circumcised. The wise men say, one that is dipped, and not circumcised, or circumcised, and not dipped, is no proselyte, until he is both circumcised and dipped.''
So the dispute ended, and it became a settled point, that one should never be reckoned a proselyte, unless he was both circumcised and dipped. And after this it became customary to receive proselytes by circumcision, dipping, and sacrifice; and the manner was this (g):
http://biblehub.com/matthew/23-15.htm