Narrated `Abdullah bin `Amr:Allah's Messenger (ﷺ) said. "It is one of the greatest sins that a man should curse his parents." It was asked (by the people), "O Allah's Messenger (ﷺ)! How does a man curse his parents?" The Prophet (ﷺ) said, "'The man abuses the father of another man and the latter abuses the father of the former and abuses his mother

English translation · Sahih al-Bukhari