Sunan Ibn Majah 46

Muhammad ibn Ubayd ibn Maymun al-Madani, Abu Ubayd, narrated to us: My father narrated to us, from Muhammad ibn Jafar ibn Abi Kathir, from Musa ibn Uqbah, from Abu Ishaq, from Abu al-Ahwas, from Abdullah ibn Masud, that the Messenger of Allah (peace and blessings be upon him) said: There are only two things: speech and guidance. The best speech is the speech of Allah, and the best guidance is the guidance of Muhammad. Beware of newly introduced matters, for the worst matters are those newly introduced; every newly introduced matter is an innovation, and every innovation is misguidance. Beware lest the passage of time grow long for you and your hearts grow hard. What is coming is near; only what is not coming is far away. The wretched person is one who was wretched in his mothers womb, and the fortunate person is one who takes admonition from another. Fighting a believer is disbelief, and reviling him is disobedience. It is not lawful for a Muslim to shun his brother for more than three days. Beware of lying, for lying is never sound, whether in earnest or in jest. A man must not promise his child and then fail to keep the promise. Lying leads to wickedness, and wickedness leads to the Fire. Truthfulness leads to righteousness, and righteousness leads to Paradise. It is said of the truthful person: He spoke truthfully and acted righteously. And it is said of the liar: He lied and acted wickedly. A person continues to lie until he is recorded with Allah as a liar.