Riyad as-Salihin (The Meadows of the Righteous)
by Imam Nawawi
263. Chapter: On the clarification of the severe prohibition against giving false witness
Allah says, "And have done with telling lies," (W22:28: 22:30) and the Almighty says, "Do not pursue what you have no knowledge of," (17:36) and the Almighty says, "He does not utter a single word without a watcher by him, pen in hand." (50:18) and the Almighty says, "Your Lord is always lying in wait." (89:14) The Almighty says, "Those who do not bear false witness." (25:72)
1550. Abu Bakr said, "The Messenger of Allah, may Allah bless him and grant him peace, said, 'Shall I inform you of the greatest of wrong actions?' We said, 'Please do, Messenger of Allah!' He said, 'Associating with Allah, disobedience to parents.' He had been reclining and now sat up and said, 'And false witness.' He continued to repeat it until we said, 'I wish he would be quiet.'" [Agreed upon]
