And the Prophet (peace and blessings of Allaah be upon him) said: “I urge you to be truthful, for “Truthfulness leads to righteousness and righteousness leads to Paradise. A man will keep speaking the truth and striving to speak the truth until he will be recorded with Allaah as a siddeeq (speaker of the truth). Lying leads to immorality and immorality leads to Hellfire. A man will keep telling lies and striving to tell lies until he is recorded with Allaah as a liar.” Narrated by al-Bukhaari, 5743; Muslim, 2607, from the hadeeth of ‘Abd-Allaah ibn Mas’ood (may Allaah be pleased with him).
It was narrated that Abu Dharr said: “The Messenger of Allah (peace be upon him) said: ‘There are three to whom Allah (the Mighty and Sublime) will not speak on the Day of Resurrection, nor will He sanctify them, and theirs will be a painful torment: The one who reminds others of what he has given them (Al-Mannan), the one who lets his Izar come below his ankles, and the one who sells his product by means of false oaths.”
Sunan an-Nasa’I, Vol. 6, Book 48, Hadith 294