Ivan was a devoted follower of Christian Orthodoxy but in his own specific manner.
He placed the most emphasis on defending the divine right of the ruler to unlimited power under God.
Some scholars explain the sadistic and brutal deeds of Ivan the Terrible with the religious concepts of the 16th century, which included drowning and roasting people alive or torturing victims with boiling or freezing water, corresponding to the torments of Hell.
That was consistent with Ivan's view of being God's representative on Earth with a sacred right and duty to punish.
He may also have been inspired by the model of Archangel Michael with the idea of divine punishment.

Despite the absolute prohibition of the Church for even the fourth marriage, Ivan had seven wives, and even while his seventh wife was alive, he was negotiating to marry Mary Hastings, a distant relative of Queen Elizabeth of England.
Of course, polygamy was also prohibited by the Church, but Ivan planned to "put his wife away".
Ivan freely interfered in church affairs by ousting Metropolitan Philip and ordering him to be killed and accusing of treason and deposing the second-oldest hierarch, Novgorod Archbishop Pimen.
Many monks were tortured to death during the Massacre of Novgorod.

Ivan was somewhat tolerant of Islam, which was widespread on the territories of the conquered Tatar khanates, since he was afraid of the wrath of the Ottoman sultan.
However, his anti-Semitism was so fierce that no pragmatic considerations could hold him back.
For example, after the capture of Polotsk, all unconverted Jews were drowned, despite their role in the city's economy.
Ivan was a devoted follower of Christian Orthodoxy but in his own specific manner. He placed the most emphasis on defending the divine right of the ruler to unlimited power under God. Some scholars explain the sadistic and brutal deeds of Ivan the Terrible with the religious concepts of the 16th century, which included drowning and roasting people alive or torturing victims with boiling or freezing water, corresponding to the torments of Hell. That was consistent with Ivan's view of being God's representative on Earth with a sacred right and duty to punish. He may also have been inspired by the model of Archangel Michael with the idea of divine punishment.
Despite the absolute prohibition of the Church for even the fourth marriage, Ivan had seven wives, and even while his seventh wife was alive, he was negotiating to marry Mary Hastings, a distant relative of Queen Elizabeth of England. Of course, polygamy was also prohibited by the Church, but Ivan planned to "put his wife away". Ivan freely interfered in church affairs by ousting Metropolitan Philip and ordering him to be killed and accusing of treason and deposing the second-oldest hierarch, Novgorod Archbishop Pimen. Many monks were tortured to death during the Massacre of Novgorod.
Ivan was somewhat tolerant of Islam, which was widespread on the territories of the conquered Tatar khanates, since he was afraid of the wrath of the Ottoman sultan. However, his anti-Semitism was so fierce that no pragmatic considerations could hold him back. For example, after the capture of Polotsk, all unconverted Jews were drowned, despite their role in the city's economy.
Ivan the Terrible