Tatbir, an act of mourning by Shia Muslims, is performed every year on the 10th day of Islamic month of Moharram, known as the Day of Ashura - Bahrain , Manama.
Performance of Tatbir
Tatbir is performed every year on the 10th day of Islamic month of Moharram, known as the Day of Ashura, and Arbaeen by the Shiites around the world. However, some Shiites also perform Tatbir on other occasions like the 21st of Ramadan (the day when first Imam Ali ibn Abi talib was martyred in Kufa), 28th of Safar (in commemoration of Prophet Mohammad's Death and Martyrdom of second Shiite Imam Hasan ibn Ali) and any time during the mourning period starting from Moharram till 8th of Rabi ul Awwal.
The practice of Tatbir includes striking oneself with a form of a sword (talwar in South Asia) on the head, causing blood to flow in remembrance of the innocent blood of Imam al Husain ibn Ali which was shed by Yazid's forces in Battle of Karbala. Some Shiites also hit their back and/or chest with blades attached to chains. This is more commonly known as Zanjeer Zani. Tatbir is performed by both men and women of all ages (the performance of women is not advertised with pictures due to Hijab reasons, however it is certainly permissible for women as it was Sayyidah Zaynab bint Ali who first performed it.
Historical evidences regarding Tatbir
The following are the few of various narrations recorded, where the Ahlul Bayt (family of Mohammad) shed their blood during mourning for Imam Hussain:
The people who practice Tatbir take lead, amongst the teachings of other infallible personalities, from Lady Zaynab, heroine of Karbala and sister of Imam Hussain. It is narrated that when Lady Zaynab saw the head of Her brother Imam Hussain being paraded in public, she hit her forehead on the bar of the carriage She was traveling in, causing blood to flow from beneath Her veil, which was visible to onlookers who witnessed the event.
Some people question this narration above and say that "Lady Zaynab was emotional at the time and didn't know what she was doing." However, the fourth Imam, Imam Zain al-Abideen, had said many times to Lady Zaynab “You are, praise be to Allah, a scholar without (the need for) a teacher, and learned without (the need for) a guide” - “Anti al-Hamdu-Lillah ‘Alimatun Ghayra Mu'allimah wa Fahhimatun Ghayra Mufahhimah” – This statement is seen by scholars as indicating that Lady Zaynab never made mistakes.
There is also a narration which states that when the tragedies of Imam Hussain were being recited in a mourning ceremony, Imam Zain al-Abideen stood up and hit his head on the wall and blood flowed from His head, and His head and His face became covered in blood.
Also, Imam al-Mahdi states in his Ziyarat Al Nahiya, addressing Imam Hussain