I don’t understand half of your thought here, but the new birth happens by believing in the death, burial and resurrection of Jesus Christ. This was not preached before the cross.
Mark 16
15 And he said unto them, Go ye into all the world, and preach the gospel to every creature.
16 He that believeth and is baptized shall be saved; but he that believeth not shall be damned.
Jn 12
34 Jesus answered him, Sayest thou this thing of thyself, or did others tell it thee of me?
35 Pilate answered, Am I a Jew? Thine own nation and the chief priests have delivered thee unto me: what hast thou done?
36 Jesus answered, My kingdom is not of this world: if my kingdom were of this world, then would my servants fight, that I should not be delivered to the Jews: but now is my kingdom not from hence.
Mark 16
21 From that time forth began Jesus to shew unto his disciples, how that he must go unto Jerusalem, and suffer many things of the elders and chief priests and scribes, and be killed, and be raised again the third day.
yeah,Jesus preach a diff gospel huh?
Now,check this out,i just happened across this in the same chapter;
11 How is it that ye do not understand that I spake it not to you concerning bread, that ye should beware of the leaven of the Pharisees and of the Sadducees?
12 Then understood they how that he bade them not beware of the leaven of bread, but of the doctrine of the Pharisees and of the Sadducees.
And what,pray tell was that doctrine Jesus opposed???
Their laws of moses.
The same thing you guys accuse Jesus of.