Musnad Abu Ya'la al-Mawsili 152:295

Abu Khaythama narrated to us, Affan bin Muslim narrated to us, Shu'bah narrated to us, Abu Ishaq said: He informed us from Abu al-Ahwas, who said: Abdullah used to say: "Lying is not appropriate, neither in seriousness nor in jest, and a man should not promise another man something and then not fulfill it for him." And Muhammad, may Allah bless him and grant him peace, said to us: "Shall I not inform you what *al-'adhah* (slander/sorcery) is? It is tale-bearing (namimah) which spreads among the people." And Muhammad said: "A man continues to speak the truth until he is recorded with Allah as a *Siddiq* (truthful one), and a man continues to lie until he is recorded with Allah as a *Kadhdhab* (great liar). Do you not see that it is said to the truthful one: 'He spoke the truth and was righteous,' and it is said to the liar: 'He lied and acted wickedly'? Indeed, truthfulness leads to righteousness, and righteousness leads to Paradise. And indeed, lying leads to wickedness, and wickedness leads to the Fire."