Idol worship is coming into the presence of a holy God on your own terms, not on God’s terms. Doing what you want because your god loves you and changes His standards as you go along. Idol worship is placing your faith in a thing of God and not in God Himself.
Idol worship also means that you have to recreate Biblical characters in your own image. Mohamed believed that Avraham Avinu (our father), King David, and even Maran Yeshua the Jewish Messiah were Muslim, and they worshiped and believed as he did. In general Christianity believes that their jesus did away with the Torah (Law) and now we live in an age of grace without Torah (no true).
We know that our holy Rabbi, Maran Yeshua was a Torah Jew, an Israelite, named Yeshua not Jesus (he never heard that name), born and raised in Israel. He is returning to the Holy Land (not to Rome) for the people of Israel, to rebuild the Holy Temple and to teach us Torah from there. Making the holy Jewish Messiah into someone he is not is idol worship. We are not to pray to him, but through his holy merit, we are to acknowledge that he is the one send from HaShem. He is the second Adam, the one after Moses, suffering like Yosef (suffering, but at the end saving the Jewish people), coming back as King David, to fight the wars of God. This is our holy King!
Maran Yeshua HaMashiach said in Mattityahu / Matthew 4:10, “You shall worship the Lord your God and Him only shall you serve.” If we worship God in spirit and in truth, we cannot worship anyone or anything else. Anything we worship, other than God, is an idol.
We must only worship God and our worship must be in spirit and in truth.