According to search-discovered classical Islamic scholarship, the act of 'attributing one's own lying inventions to Allah' (Iftira al-Kadhib 'ala Allah) is condemned as the pinnacle of injustice and a grave sin. Tafsir authorities like Ibn Kathir and Al-Tabari, in their exegesis of Quran 6:21, explain that this act is not merely lying, but a fundamental corruption of divine truth. It encompasses fabricating partners with Allah (shirk), altering His sacred law by declaring the lawful as unlawful and vice versa, or denying His clear signs and revelations. The Quran consistently poses the rhetorical question, 'And who is more unjust (adhlamu) than one who invents a lie about Allah?', emphasizing that no transgression is greater. This is because such a lie misleads humanity, challenges divine sovereignty, and destroys the foundation of faith. The linguistic root 'fa-ra-ya' points to the act of fashioning or inventing something utterly false. The Quran guarantees that such wrongdoers 'will not succeed,' signaling ultimate failure and divine retribution in this life and the Hereafter.