There are two days that are so significant for Shiite as "Taasuaa/تاسوعا And عاشورا/Ashura" ... Actually usually they use and name these two days successive. (I am aware that Imam Hussein martyred at the tenth day of Moharam as Ashura), but I wonder what the importance of Taasuaa or تاسوعا is?
In regard to the importance of Taasuaa (تاسوعا) as the ninth day of Moharam, it is quoted that Imam Jafar-a-Sadiq (peace be upon him) said:
عن الصادق (عليه السلام) قال: تاسوعاء يوم حوصر فيه الحسين (عليه السلام)
وأصحابه بكربَلاءِ واجتمع عليه خيل أهل الشام وأناخوا عليه، وفرح ابن
مرجانة وعمر بن سعد بتوافر الخيل وكثرتها واستضعفوا فيه الحسين (عليه
السلام) وأصحابه وأيقنوا انه لايأتي الحسين (عليه السلام) ناصر ولايمدّه
أهل العراق، ثم قال بابي المستضعف الغريب.
2. بحار الأنوار الجامعة لدرر أخبار الأئمة الأطهار،علامه مجلسي، اسلاميه، تهران ،ج45، ص 95.
Taasuaa is the day that Hussain and his followers were surrounded and
the army of Shaam came against him. Ibn-Ziyad and Umar ibn-Sa'd were
happy of the added army. On that day they belittled Hussain(PBUH) and
his followers and they were ascertained that no other companion would
and not even the Iraqis will come to his support. May I be sacrificed
for my weak and alone father. Bihar al-anwar. Vol.45. Pg95.
It's basically the day that Imam Hussain and his followers got to know they were finished!
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