It is narrated on the authority of Abdur-Rahman bin Abu Bakra (RA) that his father said: We were in the company of the Messenger of Allah ﷺ that he observed: Should I not inform you about the most grievous of the grave sins? (The Holy Prophet) repeated it three times, and then said: Associating anyone with Allah, disobedience to parents, false testimony or false utterance. The Holy Prophet ﷺ was reclining, then he sat up, and he repeated it so many times that we wished that he should become silent.