Hujjat ul-Islam, Aga Hajj Sayyidullah Madani has written in one of his letters as follows:

It was a religious festival, when around noon I went to visit Ayatullah Hajj Sayyid Mahmud Shahroodi, Nafaz Zakiyyah. Since it was late, people had stopped frequenting that place and he had gone into the house, but he came out once again due to his noble manners.

During conversation, he said: Once, we set out from the holy city of Kaznrnin for Ziyarat of Samarrah in the company of Late Abachi. After Ziyarat of Sayyid Muhammad, we had traveled for one Farsakh (three miles) when Aga Abachi passed out. He dropped to the ground completely motionless. Then he said: Since my death is definite, I can neither go on nor return from here, and I can do nothing for you. If you halt here, you will be putting your life into peril and it is prohibited.

So it is obligatory on you to move on and save yourself and since you can do nothing for me, there is no obligation on you. So I left him there most unwillingly and with great regret and set out from here as per my duty.

Whcn I reached Samarrah the following day and entered the inn, I saw Aga Abachi coming out. After greetings, I asked him how he managed to reach there before me. He replied: Yes, as you know, I was on the verge of death and no other option was there.

So I straightened my legs, closed my eyes and started waiting for death. When I heard the wind blow, I thought that it was the angel of death and opened my eyes, but when no one was seen, I closed my eyes again. Once I heard someone and opened my eyes to see that it was an Arab gentleman in ordinary Arab garments, holding the reins of a mule. He was standing near me. He asked me how I was and why I was lying in that wilderness. I replied that my whole body was in pain. I had no strength to move and I was waiting for death.

He said: Get up, I'll escort you. I replied: I cannot get up. He picked me up and made me mount. I noticed that wherever he touched me, the pain disappeared; till his hand gradually reached to all the parts of my body and the whole body became so comfortable as if there was no exhaustion in the first place. He was pulling the rein of the mount. I requested him to mount as well, but he didn't agree.

He said: I am used to walking. Just then I noticed that he had a green shawl around his waist. I said to myself: Are you not ashamed that a Sayyid and a descendant of the Messenger of Allah (S) should walk ahead leading your mount and you sit on the mount? At once I jumped down from the mount and said: Master, I sincerely want you to mount. At that moment, I found myself in an inn and no one else was present there. (Dated: 29th Rabius Thani, 95 A.H.)

A similar story is that, which Ayatullah Sayyid Shahabuddin Marashi has narrated from the late gentleman in the book of Muntaqim Haqiqi, Pg. 175. It is quoted here for more insight.