The vigilant believers consider the status of du’a’ Kumayl among other du’a’s as the status of man among the other creatures of the Almighty. In other words, they know du’a’ Kumayl as “Insan al-Ad’iyah”. The great scholar, researcher and reporter of ahadith, Allamah Majlisi regards du’a’ Kumayl as the best du’a’. Allamah Majlisi narrates from “Iqbal” of Sayyid Ibn Tawus in his book “Zad al-Ma’ad”:
Kumayl said: “One day, I was with my master ‘Ali (as) in Kufah. We were talking about Sha’ban the fifteenth. Imam said: “One who spends that night worshipping and recites du’a’ Khidhr, his prayer will be answered for sure.” When Imam (as) returned home, I went to him. He said: “What do you want?” I answered: “I’ve come to you so that you may teach me du’a’ Khidhr.” He told me to sit down.
Then he said: “O Kumayl! When you memorize this du’a’, recite it every Thursday night, or once in a month, or once in a year or once in your lifetime, and Allah will save you from enemies, help you, extend your sustenance, and forgive your sins. O Kumayl! Your extended and faithful service has made me teach you such a blissful du’a’.” Then he said: “Write it down!” And he then recited it to me.
The divine theologist, Kaf’ami, writes in his book ‘Misbah’: “Amir al-Mu’minin (as) recited this du’a’ in prostration.”1
The supplicant should recite this du’a’ on Thursday night, facing the direction of the qiblah, sincerely and humbly. This way the supplication is more likely to be answered.2 The supplicant should also present himself before Allah with a tearful eye which is so valuable before the Almighty that it hastens the forgiveness of sins and attraction of His blessings.3
It is narrated from Imam Sadiq (as):
مَا مِنْ شَيْءٍ إلاَّ وَلَهُ كَيْلٌ وَوَزْنٌ، إلاَّ الدُّمُوعَ؛ فَإنَّ القَطْرَةَ تُطْفِئُ بِحَاراً مِنَ النَّارِ، وَلَو أنَّ باكِياً بَكَى فِي أُمَّةٍ لَرُحِمُوا.
Everything has a special scale except tears; a drop of tear extinguishes oceans of fire. Allah forbids inferno from burning a tearful eye. In fact if there’s one tearful person (from Allah’s fear) in any nation, all the people will be forgiven.4
كُلُّ عَيْنٍ بَاكِيَةٌ يَوْمَ القِيَامَةِ إلاَّ ثَلاثَةً: عَيْنٌ غُضَّتْ عَنْ مَحَارِمِ اللهِ، وَعَيْنٌ سَهِرَتْ فِي طَاعَةِ اللهِ، وَعَيْنٌ بَكَتْ فِي جَوْفِ اللَّيْلِ مِنْ خَشْيَةِ اللهِ.
All the people are tearful in the Hereafter except three: one who closes his eyes to what Allah forbade, one who remains alive for Allah, and one cries for the fear of Allah at midnight.5