Perhaps the capstone on this turning point in Christianity from an acceptance to a rejection of Judaism is Melito of Sardis (circa AD 170), who turned the Apostles’ charges against specific characters in history on the entire Jewish race, when he said, effectively, you [Jews] murdered God
. Since Christianity had now far removed Judaism from itself and given it the status of a failed religion, it was easy for church fathers like Melito to condemn the entire Jewish race. Tertullian, writing at the end of the second and beginning of the third century, took the example of those specific Jews who had failed to recognize Yeshua in New Testament times and universalized it so that he could say the Jews themselves had rejected Yeshua. Judaism itself has rejected and killed YHWH, therefore Christianity has replaced it in everything from authority to inspiration. On that grossly errant path, it would continue to walk.
One consequence of Christianity’s break with Judaism and replacement of it with itself was the fact that, unchecked by Judaism, Christianity developed a myth of prophetic inspiration concerning the entire Greek LXX. Justin and all those apologists after him would spend a great deal of time arguing with Jews about why the LXX and all its differences from the Hebrew scriptures in content as well as additional books, were true, inspired scripture. Augustine would eventually explain away the inconsistencies between the Christian LXX scriptures and the Hebrew scriptures by doing what Justin had done before him—trumping facts, evidences, and arguments by appeal to the Holy Spirit. Augustine contended that both the LXX and the Hebrew were equally inspired—even where they differed and conflicted—because there was not a single meaning in scripture or prophecy, but multiple meanings. Therefore, Augustine was able to claim the Spirit had correctly inspired the meanings and texts in the LXX which differed from the meanings and texts in the Hebrew scriptures. Just one church father rejected the myth of the LXX’s prophetic inspiration—but only temporary (Jerome).
Although a few Christians would seek to return in some way to Judaism (like Jerome and Origen, who took Jews as teachers and tutors to come to a better understanding of scripture), this would now be the exception, not the rule. Judaism would have a say only insofar as it agreed with the decisions and beliefs of gentile Christians. Christianity had cut itself off from the tree onto which it was grafted and its withered, dead fruit remains to this day.