Orthodox Islam and Christianity each deemed the other’s core doctrine heretical

Evidence

What has been at issue in orthodox Islam is not the status of Jesus but that of Christianity, and 0f the way Jesus surfaces in Christian belief. For if orthodox Christianity regards Islam as a heresy, orthodox Islam has historically regarded some of the main tenets of Christianity as altogether blasphemous: the idea of the Trinity, the idea of Jesus as a Son of God, the further idea that Mary was a virgin, the even more scandalous idea of the Holy Ghost. The legacy of the Crusades lives, we might recall, on both sides of the orthodox divide. — Aijaz Ahmad, In Theory, 784

Categorization

• XREF: Symmetric heretic-vs-blasphemy framing supports Ahmad’s point that religious difference runs on mutual orthodoxy rather than a unilateral Western view of the Orient. — connects to: Medieval Christians saw Islam as doubly heretical, overlapping both their faith and Judaism — Norman Daniel, Islam and the West, 1059; Both medieval Christianity and Islam defined each other by disagreement, not overlap — Norman Daniel, Islam and the West, 1080; Medieval Christian polemic framed Islam alongside heresy and Judaism — Norman Daniel, Islam and the West, 1045 (+1 more)

Broader Connections

• Medieval Christians saw Islam as doubly heretical, overlapping both their faith and Judaism #expands (0.90) — Norman Daniel, Islam and the West, 1059
• Both medieval Christianity and Islam defined each other by disagreement, not overlap #expands (0.85) — Norman Daniel, Islam and the West, 1080
• Medieval Christian polemic framed Islam alongside heresy and Judaism #exemplifies (0.80) — Norman Daniel, Islam and the West, 1045