Source: The Great Interpretation of Dreams (Ibn Sirin)
Reciting the Quran backwards indicates abandoning religion, following desires, and misguidance.
Source: Perfuming Humanity in the Expression of Dreams (Al-Nabulsi)
Reciting the Quran backwards indicates committing heresy or speaking falsehood.
Source: Signs in the Science of Expressions (Ibn Shaheen)
Reciting the Quran backwards is interpreted as misguidance and worry.