Salaamun Alaikum
SHAFAQNA – Imam Sajjad (AS) had severe stomach ache in Karbala to an extent that he could not carry weapons or fight [1,2,3]. The illness started in Karbala and not from the time Imam Hussain (AS) started his journey towards Iraq. Of course his illness was a divine plan so that one child would remain from Imam Hussain (AS) to undertake the Imamate and the leadership of Muslims.
[1] Basaerul Darajat, Saffar Qomi, Pages 148 and 163.
[2] Alershad, Sheikh Mofeed, Page 114.
[3] E’alammul Wara, Tabarsi, Page 246.
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