Abu Mohammad Reqqi narrated:

I went to see Imam Ridha/Reza (AS) and greeted him and he answered and asked how I was and talked to me until he said: O’ Abu Mohammad, any servant of God who is inflicted with a calamity, and he/she tolerates it and is patient, definitely will be rewarded the reward of martyrs by God. I told myself why did Imam say these words as there was no talk of calamity and illness, what does it mean, why Imam (AS) say this sentence?

I said farewell and came out and caught up with my friends. Suddenly I felt pain in my legs, and I spend all night in pain. In the morning I noticed my legs are swollen and after a while the swelling increased. I remembered what Imam (AS) said about being patient when inflicted with calamity which I did not understand at the time. I returned to Medina in that situation, a large wound appeared in my leg as a result of infection. It was very difficult and I could not tolerate it and I realized that Imam (AS) said those words for me to keep calm and be patient and this illness lasted for two months. It is narrated that Abu Mohammad regained his health after a while and then became ill again and died of his illness [1].

[1] Beharul Anwaar, Vol. 51, Page 49.

Source: en.shafaqna.com