Per the Bible, the early Christians (and Jesus/Yeshua, himself), specifically all but one author of the New Testament (Luke, a Greek physician who wrote the books of Luke and Acts), were Hebrew (or “Jewish” to use the less accurate/nuanced word in this case). However, they shunned the Rabbinical traditions, pharisaical “legalism,” and extra-scriptural rites and ceremonies, and were strict followers of Mosaic Law/Torah, per Jesus’ own guidelines and teachings. When Jesus was executed and the Temple Veil torn in half, the sign was clear - the Temple in Jerusalem, specifically, the inner chamber, was no longer where God would abide. The “chosen” had killed His Son, blaspheming Him, rejecting His message, authority, and most egregiously, his role as the physical incarnation of the One True God. What followed, according to scripture, subsequent to Christ’s resurrection and ascension, was a complete departure from even lip service obedience to “Jewish” control of The Temple Priesthood. Christ’s eleven (and shortly after, thirteen, including Matthias who replaced the traitor Judas and Paul) Hebrew apostles received special revelation as well as sign gifts that affirmed their office (miracles, healings, special knowledge they couldn’t have had naturally) and moved forward intent on leading their fellow Hebrew people to follow Christ and restore their relationship with the One True God. For their efforts, they were maligned, assaulted, and executed by their Babylonian blood ritual “brothers,” who asserted that Jesus was a liar, the son of a whore, and was in hell, boiling in feces for eternity. To sum up briefly, the authors of the Bible were mostly Hebrew, or “Jewish,” with the Old Testament being written in Hebrew, while the New Testament was written in Greek.