Abdur-Rahman bin Abi Bakrah narrated from his father who said: " The messenger of Allah said: “Shall I not tell you of the biggest of the major sins?' they said : “Of course! O Messenger of Allah!' He said: “To join partners with Allah, and disobeying one's parents.'"He said : " He sat up, and he had been reclining. He said: “And false testimony, or false speech.' And the Messenger of Allah would not stop saying it until we said (to ourselves): “I wish that he would stop”””””"
SahihSahihHasan SahihBook 27 · Hadith 5