The Quran states that Jewish and Christian scriptures were corrupted. This OpEd is about charges from before the Quran and mostly is about debates within Judaism and Christianity.
Tahrif Charges Prior To The Qur’an – OpEd
Rabbi Elazar ben Yossi HaGelili who lived in the first half of the 2nd century C.E. said: “I said to the Cuthite scribes: You falsified the Torah and gained nothing from that. For you wrote “near the terebinths of Moreh near Shechem,” [“near Shechem” being an addition by the Cuthites to the Samaritan Torah]. (Sifre on Deuteronomy piska 56)...
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Organized Judaism from the Rabbinic period onwards always considered the Masoretic Text as the only (kosher) text of the Bible, and thus the “original text” of the Hebrew Bible. The rabbis describe the Samaritan Torah as a falsification (Tahrif) of the Jewish Torah (Jerusalem Talmud Sotah 7.3; Babylonian Talmud Sotah 33b; and Sanhedrin 90b) and the few Samaritan additions to its text were never quoted in rabbinic literature.
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Independently, Mani. who lived in Persia from 216-274 C.E. and was the founding prophet of the Manichaean religion, charged all the other then existing sacred scriptures with tahrif
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A principal critique Mani levels against some of his prophetic predecessors is that they failed to insure the accurate registration and preservation of their writings, and so these writings; which eventually evolve into the canonical scriptures associated with religions like Buddhism, Zoroastrianism, Judaism, and Christianity; were corrupted and falsified by later generations of disciples and followers.
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Christian polemicists have used tahrif claims since the time of Justin Martyr (c.100-165 C.E.), who was born of pagan parents. By 132 C.E. he had become a Christian and by the 140’s began charging Jews with the alteration of those portions of Jewish scripture which purportedly predicted the advent of Messiah Jesus and the Christian Church.
Tahrif Charges Prior To The Qur’an – OpEd
Rabbi Elazar ben Yossi HaGelili who lived in the first half of the 2nd century C.E. said: “I said to the Cuthite scribes: You falsified the Torah and gained nothing from that. For you wrote “near the terebinths of Moreh near Shechem,” [“near Shechem” being an addition by the Cuthites to the Samaritan Torah]. (Sifre on Deuteronomy piska 56)...
...
Organized Judaism from the Rabbinic period onwards always considered the Masoretic Text as the only (kosher) text of the Bible, and thus the “original text” of the Hebrew Bible. The rabbis describe the Samaritan Torah as a falsification (Tahrif) of the Jewish Torah (Jerusalem Talmud Sotah 7.3; Babylonian Talmud Sotah 33b; and Sanhedrin 90b) and the few Samaritan additions to its text were never quoted in rabbinic literature.
,,,
Independently, Mani. who lived in Persia from 216-274 C.E. and was the founding prophet of the Manichaean religion, charged all the other then existing sacred scriptures with tahrif
...
A principal critique Mani levels against some of his prophetic predecessors is that they failed to insure the accurate registration and preservation of their writings, and so these writings; which eventually evolve into the canonical scriptures associated with religions like Buddhism, Zoroastrianism, Judaism, and Christianity; were corrupted and falsified by later generations of disciples and followers.
...
Christian polemicists have used tahrif claims since the time of Justin Martyr (c.100-165 C.E.), who was born of pagan parents. By 132 C.E. he had become a Christian and by the 140’s began charging Jews with the alteration of those portions of Jewish scripture which purportedly predicted the advent of Messiah Jesus and the Christian Church.