Introduction

The tongue is among the most consequential of the human faculties in Islamic ethics. A single word can earn the speaker a degree in Paradise or cast them into the Fire, as the Prophet Muḥammad warned in a hadith of chilling directness preserved in the Ṣaḥīḥayn. The Islamic scholarly tradition recognized early that despite its smallness, the tongue is the instrument of more sins than perhaps any other limb, and scholars across the centuries dedicated substantial portions of their ethical and legal writings to cataloguing its dangers and prescribing the disciplines that guard it. Among the most concise and influential works in this genre is that attributed to Imam Yaḥyā ibn Sharaf al-Nawawī (631-676 AH / 1233-1277 CE), who either authored or whose name became associated with a treatise on the sins of the tongue that has been widely circulated under the title Al-Āfāt al-Lisān or similar designations. Al-Nawawī's scholarly authority, established through his contributions to Shāfiʿī jurisprudence, hadith criticism, and Islamic ethics, gave such works a credibility that ensured their long circulation and study.

The subject of guarding the tongue (ḥifẓ al-lisān) in Islamic ethics covers a defined and serious set of transgressions. Lying (kadhib) is forbidden by clear Quranic verse and multiple authenticated hadiths, with the Prophet describing it as a path that leads to wickedness (fujūr) and ultimately to the Fire. Backbiting (ghībah) is likened in the Quran to eating the flesh of one's dead brother, a graphic prohibition that the scholars explain covers any mention of a Muslim in their absence with what they would dislike, even if true. Slander (buhtān) adds falsehood to the injury of backbiting and is therefore worse. Tale-carrying (namīmah), which involves conveying statements between people with the intent of causing harm or discord, is among the major sins (kabāʾir), as is mockery (sukhriyyah) of believers. False oaths (aymān kādhiba) compound lying with the gravest form of disrespect for the name of God. A work on the tongue's dangers treats each of these categories with Quranic and hadith evidence, practical examples, and guidance on repentance and remedy.

The scholarly lineage behind this genre stretches from the Companions and Successors through the great ethical synthesizers of the classical period. Imam al-Ghazālī devoted an entire volume of his Iḥyāʾ ʿUlūm al-Dīn to the calamities of the tongue (āfāt al-lisān), and al-Nawawī's treatment can be read alongside and as a complement to that more expansive discussion. Later scholars, including Ibn al-Qayyim al-Jawziyyah, addressed the diseases of the tongue within broader frameworks of spiritual medicine for the heart. What distinguishes a work in this lineage is its insistence that silence in the face of temptation to speak evil is itself a form of worship, and that the believer who disciplines the tongue is engaged in one of the most rewarding forms of continuous self-striving (mujāhadah).

The reader who takes up this work is invited to conduct an honest personal audit. The sins catalogued here are not the offenses of villains but the everyday failures of ordinary believers who may have internalized cultural habits of gossip, casual dishonesty, or thoughtless speech without recognizing them as religiously serious transgressions. Al-Nawawī's approach, grounded in revelation rather than personal opinion, provides the reader with the authoritative foundation needed to take these matters seriously. The remedy begins with knowledge of what is prohibited, continues with the cultivation of mindful awareness of one's speech, and is sustained by the practice of remembrance of God (dhikr) as an alternative to idle or harmful talk. Reading this work with sincere intention to reform one's speech is itself an act of worship, and the benefits of such reform extend outward into every relationship the believer has with family, community, and God.