It is common to find many Muslims involved in misusing the tongue, without even recognising its inherent evil consequences. Regarding to this effect, the Messenger of Allah also said: The servant says something that he thinks is harmless, and for which he will be plunged into the depths of the Fire for seventy autumn (years). In this booklet, the author has delivered details on the evil of the tongue and its harms for the Deen and society, in the light of the Quran and authentic Sunnah.