What does Arbaeen teach us?

If during the long days of their captivity, Zaynab al-Kubra (pbuh) and Imam Sajjad (pbuh) had not revealed the truth of Ashura's philosophy and Hussain bin Ali’s (pbuh) purpose, news of the event of Ashura would not have remained and stayed so energetically alive to this day. In those days, the oppressive powers made full use of false, biased propaganda as they do today. The lesson that Arbaeen teaches us is that we must keep the memory of truth and martyrdom alive in the face of the storm of the enemy’s propaganda.

Imam Khamenei, [Sept. 20, 1989]