Islam is a heresy, according to Saint John of Damascus in his "Critique of Islam":
"There is also the superstition of the Ishmaelites which to this day prevails and keeps people in error, being a forerunner of the Antichrist. They are descended from Ishmael, who was born to Abraham of Agar, and for this reason they are called both Agarenes and Ishmaelites. They are also called Saracens, which is derived from Sarras kenoi, or destitute of Sara, because of what Agar said to the angel: 'Sara hath sent me away destitute.' These used to be idolaters and worshiped the morning star and Aphrodite, whom in their own language they called Khabár, which means great. And so down to the time of Heraclius they were very great idolaters. From that time to the present a false prophet named Mohammed has appeared in their midst. This man, after having chanced upon the Old and New Testaments and likewise, it seems, having conversed with an Arian monk, devised his own heresy. Then, having insinuated himself into the good graces of the people by a show of seeming piety, he gave out that a certain book had been sent down to him from heaven. He had set down some ridiculous compositions in this book of his and he gave it to them as an object of veneration."
Muslims believe the following...
Arius, the bishop from Egypt, like many of the early Christians, believed in God as One and Jesus, peace be upon him, as one subservient to God. That is to say, in a lessor position than God.
This concept is still held today by more than 1.5 billion Muslims, who adhere to the teachings of the Quran and the prophet Muhammad, peace be upon him.
Islam is a bastardization of the Jewish and Christian faiths. The former being made by eternal covenant with God...the latter be fulfilled in Jesus Christ, the Son of God. It makes a prophet out of a false prophet, Muhammad. And I believe their attempt to bring forth the 12th IMAM will be the beginning of the end. Therefore my insight into WHY ISLAM IS THE WHORE OF BABYLON
I wrote that research in a book in the late 70's - early 80's... which I guess seemed so extreme at that time that I could not get it published... Like Frank Herbert's DUNE [1984] used all those Islamic terms without much alarm.
Of course today one needs only the guidance of John 10:10 - the thief comes to steal, kill and destroy.
God shall send them strong delusion... 2 Thessalonians 2:11 {KJV}