What is the ruling on eating glass and participating with it in festivals if it does not harm the performer, and is it permissible to invite him to present it in Da'wah camps?

Eating glass and similar acts are acts of sorcery and forbidden magic, and are not from the miracles (karamat) of saints or signs of righteousness. Rather, the allies of Allah are the people of faith and piety. It is not permissible to participate in these gatherings or to invite those who present them, and it is obligatory to denounce them and warn against them. Attention should also be paid to the word "festival" (مهرجان), as its origin is a Persian holiday.