Idolatry is the worship of anything that isn't God.
According to the the 13 Principles of Judaism, God cannot take a physical or material form. Spinoza was excommunicated for claiming with his pantheism that the Universe was God.
https://web.oru.edu/current_students/class_pages/grtheo/mmankins/drbyhmpg_files/GBIB766RabbLit/Chapter9Maimonides13Princ/index.htmlJews are forbidden to enter churches which are places of abomination where idolatry is practised.
https://www.yeshiva.co/ask/6517According to the Christian narrative, Jesus was convicted of blasphemy.
https://www.bbc.co.uk/bitesize/guides/z6b96v4/revision/4According to the Doctrine of the Trinity, Christians are required to worship Jesus as the co-equal of the God of Israel who is also Allah, which is the idolatrous worship of a man convicted and crucified for blasphemy against the Abrahamic God.
https://en.wikipedia.org/wiki/Trinity#One_God_in_three_personsIn Trinitarian doctrine, God exists as three persons but is one being, having a single divine nature. The members of the Trinity are co-equal and co-eternal, one in essence, nature, power, action, and will. As stated in the Athanasian Creed, the Father is uncreated, the Son is uncreated, and the Holy Spirit is uncreated, and all three are eternal without beginning. "The Father and the Son and the Holy Spirit" are not names for different parts of God, but one name for God because three persons exist in God as one entity. They cannot be separate from one another. Each person is understood as having the identical essence or nature, not merely similar natures.https://en.wikipedia.org/wiki/Athanasian_Creed#ContentJudaism and Islam are agreed on the oneness of God. It is only Christians who claim that Jesus is co-equal, co-substantial and co-eternal with God, making them the odd one out.
I would define blasphemy as anything said or done that would be offensive to God if He exists. It is the Christian narrative that Jesus was convicted of blasphemy.
Restoring Truth, Logic and Morality with Secular Koranism