Sahih Al Bukhari – Book of Good Manners And Form (Al-Adab)

Volumn 008, Book 073, Hadith Number 116.
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Narated By ‘Abdullah : The Prophet said, “Truthfulness leads to righteousness, and righteousness leads to Paradise. And a man keeps on telling the truth until he becomes a truthful person. Falsehood leads to Al-Fajur (i.e. wickedness, evil-doing), and Al-Fajur (wickedness) leads to the (Hell) Fire, and a man may keep on telling lies till he is written before Allah, a liar.”