Hazrat Moulana Muhammad Ilyaas (rahmatullahi ‘alaih) once mentioned:
The tongue plays an important role in causing one to earn distinguished positions. If a person utilizes the tongue for good, and makes it the means for carrying out righteous works (e.g. he commands people to obey Allah Ta‘ala, recite the Quraan Majeed etc.), then he will be distinguished and recognized among people for the good which he carried out through his tongue (i.e. in this world and the Hereafter, he will be recognized for acquiring great rewards and a high rank on account of utilizing his tongue for good).
However, if he makes his tongue a tool for carrying out evil works and sins through involving himself in obscene speech or through verbally abusing people, then through this very tongue, he will be distinguished and recognized among people (in this world and the Hereafter) for the wrong works and evil deeds that he excelled in. At times, on account of the evil deeds carried out through this tongue, a person debases himself to such an extent that he becomes worse than a dog or even a swine. In regard to the use of the tongue and its consequences, the hadeeth shareef mentions:
وهل يكب الناس في النار على وجوههم أو على مناخرهم إلا حصائد ألسنتهم
There is nothing that causes people to fall into Jahannum upon their faces or noses more than the harvest of their tongues (i.e. on account of the evil deeds that they earn through their tongues e.g. lying, slandering, backbiting, carrying tales, etc. they will be thrown headlong in the fire of Jahannum) (Sunan Tirmizi #2616)
(Malfoozaat Hazrat Moulana Muhammad Ilyaas (rahmatullahi ‘alaih) pg. 22)