Of the 12 Hebrew tribes, Judah was the most faithful and the most active in making converts, especially after they teamed up with the Levites.
“For the Levites left their suburbs and their possession, and came to Judah and Jerusalem: for Jeroboam and his sons had cast them off from executing the priest’s office unto the LORD.” 2 Chronicles 11:14
Their converts became known as the proselytes (i.e., the ones who prayed to Jehovah, the God of Judah).
“Judahites and proselytes…“ Acts 2: 11
The other 10 tribes, collectively known as Israel, separated from Judah and always did evil in God’s eyes.
“Ephraim compasseth me about with lies, and the house of Israel with deceit: but Judah yet ruleth with God, and is faithful with the saints.” Hosea 11:12
So while Judah was helping the priests in the implementation of their office, Israel was basking in evil. Thus Judah became the one that carried the torch of God’s light unto the nations.
It was a process that would culminate with the advent of Jesus the Christ and His church assembly. Because, just like the Christian Church, the Judahite Hebrew nation was a proselytizing nation that wanted people all over the world to know and pray to the true God of the Universe; even though, at one point, the conversion process had become totally corrupted because of the pharisaic teachings. Let’s hear Jesus:
“Woe unto you, scribes and Pharisees, hypocrites! for ye compass sea and land to make one proselyte, and when he is made, ye make him twofold more the child of hell than yourselves.” Matthew 23:15
Later on, those proselytes, who obviously were not Judahite Hebrews and who adhered to the pharisaic teachings, became known as Rabbinists, while their religion was called Pharisaism/Rabbinism, and their “holy writ” was entitled the Talmud, a Babylonian book full of lies and superstitions.
In the 18th Century, those very same Rabbinists hijacked the words Jew and Judaism, in order to change their appellation along with that of their religion (just like when Blacks didn’t want to be called Negroes no more). A change that was purely cosmetic, as their beliefs, which are still found in their enduring and cherished Talmud, did not change one iota.
The idea behind such superficial name changes was to deceive the world into thinking they were the Judahite Hebrews of the bible.
And what was their reason for wanting to hoodwink the world? See How the Ashkenazi Jews Conquered the West.