Mourning for Imam Husayn (a) is to commemorate the event in which virtue stood against vice and the blood of the oppressed overwhelmed the swords and spears of the oppressors. Therefore, mourning for the martyrs of Karbala in addition to expressing our grief over their loss, especially in such a brutal manner, and showing respect for their bravery and sacrifice, is to attain insight and motivation to follow their path by taking them as our role models. Therefore, a union is to be shaped and strengthened between those who mourn and those who are mourned for.

The emotional essence of this unity is sadness and grief. This would reach its climax when one’s tears overflow for the martyrdom of Imam Husayn (a) and his companions. The prerequisite for this sadness is to understand the tragic incidents of the event of Karbala and its aftermath. This event affects any person who comes to know about these incidents.

The intellectual essence of this unity is to acknowledge the manifested virtues and values that Imam Husayn (a) and his party demonstrated and to resemble them in the best way possible. To truly mourn and feel sad over a teacher who spent and gave his life making an effort to teach those in need of knowledge is to appreciate his accomplishments and to safeguard and continue his unfinished tasks. We are to truly mourn for a doctor who took risks by travelling to remote and unsafe places to treat the ill and consequently gets killed for a number of reasons. Such a person deserves our respect. We are to emulate him and continue his job. To merely look sad or cry is not enough; it does not fully demonstrate one’s loyalty and unity with the lost ones.

References

https://www.quora.com/What-is-the-true-meaning-of-mourning-for-Imam-Hussain/answer/Ali-Mehrabani-1?ch=18&oid=1477743682005568&share=7960a246&srid=hyfRI3&target_type=answer