Abdul Qadir Jilani (1077–1166 CE) was a very influential and powerful Persian preacher, mystic and Sufi. He was born in Gilan, Iran but was based largely in Baghdad. The Qadiri Sufi Order is named after him.
Remembering death is a remedy for the diseases of the lower self. I have spent years remembering death frequently, by night and day. I have prospered by remembering it, and I have overpowered my lower self through that remembrance.
One night I remembered death and wept from the onset of night until the beginning of dawn. I kept on weeping and saying, “O Allah, I ask You that the Angel of Death does not take my soul away but that You do.” At the beginning of dawn, my eyes dozed off and I saw a handsome old man with beautiful features coming in through the door.
I said to him, “Who are you?”
He replied, “I am the Angel of Death.”
I said to him, “I have asked Allah (mighty and glorious is He) that He, not you, would take away my soul.”
He asked, “But why did you ask Him for that? I am just a servant following orders. I am commanded to be gentle to some people and rough to others.”
He then embraced me and wept, so I wept with him. I then woke up while I was still weeping.
Translation Shetha Al-Dargazelli & Louay Fatoohi