The Talmud asks an interesting question regarding the Ten Commandments. If they are so important and they represent fundamental beliefs in Judaism, why are they not incorporated into our daily prayers? A suggested place would be to recite the Ten Commandments right after the morning Shema.
The reason given by the Gemara was that because of the arguments of the heretics, the Torah would be undermined. The uncensored Rashi describes these heretics as גוים תלמידי ישו, meaning Gentiles, the students of J.C. They will claim that only the Ten Commandments are true as they were given directly by G-d to the Jewish people. But the rest of the Torah is false,(G-d forbid).
The Rabbis determined that it was better to leave them out so as not to fan the flames of heresy and falsehood.