The last afternoon before the battle
Tasu'a is the ninth of Muharram. On that afternoon in 61 AH Shimr b. Dhi l-Jawshan arrived at Karbala carrying Ibn Ziyad's final letter to Umar b. Sa'd: either force Husayn (a) to surrender and fight him if he refused, or hand the command to Shimr. Ibn Sa'd kept the command and moved his lines forward against the camp in the evening.
The night asked for
Imam Husayn (a) sent Abbas (a) to ask the enemy for one night's respite, so that his companions could spend it in prayer, recitation of the Qur'an and supplication. The request was granted. That same day Shimr — a kinsman of Umm al-Banin — brought a written safe-conduct for her four sons; Abbas and his brothers refused it outright, asking how they could accept safety while the grandson of the Prophet (s) had none.
Why the day belongs to Abbas
Because of that refusal, and because of his role as commander and water-bearer of the camp, the Shia have long given the ninth of Muharram to Abbas (a). Majalis on this day recount his loyalty, and in many communities the processions of Tasu'a are as large as those of Ashura itself.
Written for Shia Online Community. Dates and facts are checked against the references listed under Research & books; where the tradition records more than one date, all are given.
