ما هي كفارة قذف قبيلة الصاحب على سبيل المزاح؟

The basic principle is that joking is permissible as long as it does not involve anything forbidden, such as lying, frightening a Muslim, or harming him. This is based on what Bahz ibn Hakim narrated from his father, from his grandfather, that the Prophet, peace and blessings be upon him, said: "Woe to him who speaks and lies to make people laugh; woe to him, then woe to him." As for slandering a tribe or a town, or insulting them with something other than slander, it is forbidden and requires repentance. There is no prescribed hadd punishment for it, but rather a discretionary punishment (ta'zir), because there is no shame on the slandered and because the lie of the slanderer is certain. Thus, it is like insulting them with something other than slander.