Does Torah View Christianity As Idolatry? Islam?

Punishments for Jews Who Practice Christianity and/or other Religions

http://www.mechon-mamre.org/i/1503.htm#14

Hilcoth Teshuvah 3:14

The following individuals do not have a portion in the world to come. Rather, their souls are cut off and they are judged for their great wickedness and sins forever:

• the Minim
• the Apicursim
• those who deny Torah
• those who deny the resurrection of the dead and the coming of the redeemer
• those who rebel against G-D
• those who cause the many to sin
• those who separate themselves from the community
• those who proudly commit sins in public as Yehoyaqim did
• those who betray Jews to Gentile authorities
• those who cast fear upon the people for reasons other than the service of G-D
• murderers
• slanderers
• one who extends his foreskin

Five Individuals are described as Minim:

• one who says there is no G-D or ruler of the world
• one who accepts the concept of a ruler, but maintains that there are two or more
• one who accept that there is one Master, but maintains that He has a body or form
• one who maintains that He was not the sole First Being and Creator of all existence
• one who serves a star, constellation, or other entity so that it will serve as an intermediary between him and the Eternal Lord.

Each of these five is a min

Three Individuals are described as Apicursim:

• one who denies the existence of prophecy and maintains that there is no knowledge communicated from G-D to the hearts of men
• one who disputes the prophecy of Moses, our teacher
• one who maintains that the Creator is not aware of the deeds of men.

Each of these three individuals is an Apicurus

There are three individuals who are considered as "one who denies the Torah":

• one who says Torah, even on verse or one word, is not from G-D. If he says: "Moses made these statements independently," he is denying the Torah.
• one who denies the Torah's interpretation, the oral law, or disputes [the authority of] its spokesman as did Tzadok and Beitus
• one who says that though the Torah came from G-D, the Creator has replaced one mitzwah with another one and nullified the Torah, for example, the Arabs...

Each of these individuals is considered as one who "denies the Torah."