All across the world, and even in the UK we see strange practices taking place on and around the day of Ashura each year by the shi’ite Muslims, where they wail and shout out their supposed grief, even going as far as to hit themselves, or even to get whips and blades and beat and cut themselves in the mock rituals of mourning.
For the sons of mutah who cut themselves and hit themselves in the face on Ashura, you should know Imam Hussain alayhi salaam is free from your acts of jahiliyyah (ignorance).
Imam Hussain alayhi salaam shortly before his demise, had advised his beloved sister Sayyidah Zainab (Radhiallaahu Ánha) not to mourn over his death in this manner. He said, “My dear sister, I swear upon you that you, in case I die, shall not tear your clothes, nor scratch your face, nor curse anyone for me or pray for your death”.
Al-Kamil, ibn Kathir vol. 4 pg. 24