Messenger of Allah (ﷺ) said, "It is one of the gravest sins to abuse one's parents." It was asked (by the people): "O Messenger of Allah, can a man abuse his own parents?" Messenger of Allah (ﷺ) said, "He abuses the father of somebody who, in return, abuses the former's father; he then abuses the mother of somebody who, in return, abuses his mother".

[Al-Bukhari and Muslim].

Another narration is: Messenger of Allah (ﷺ) said, "One of the major sins is to curse one's parents". It was submitted: "O Messenger of Allah! How can a man curse his own parents?" He (ﷺ) said, "When someone curses the parents of another man who in return abuses the former's father; and when someone abuses the mother of another man who in return abuses his mother."