Ruling on ascribing a person to Judaism or Christianity
What makes a person a Jew or Christian, is it by performing their deeds or studying their knowledge?
A person becomes a Jew if they believe in the beliefs of the Jews and act upon them. Likewise, they become a Christian if they believe in the beliefs of the Christians and act upon them. Just studying their knowledge, beliefs, and practices to understand the falsehoods and refute them, does not make someone a Jew or a Christian.