The Prophet ﷺ 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." (Using translation from Bukhārī 6094)
"إِنَّ الصِّدْقَ يَهْدى إِلى الْبَرِّ، وَإنَّ الْبَرَّ يَهْدى إِلى الْجَنة، وَإنَّ الرَّجُلَ لَيَصْدُقُ حتَّى يُكْتَبَ عنْدَ الله صِدِّيقًا، وَإِنَّ الْكَذِبَ يَهْدى إِلى الْفُجُورِ، وإن الْفُجُورَ يَهْدِى إِلى النَّارِ، وإِنَّ الرَّجَلَ لَيَكْذِبُ حتَّى يُكْتَبَ عِنْدَ الله كَذَّابًا".