The Dua-e Ahad (Arabic: دعاء العهد) is an Arabic language allegiance supplication prayer to [Mahdi (ajtf], twelfth Imam of Shia Islam (the Imam Mahdi).
Ja'far al-Sadiq had a hadith about important of recite the supplication in every morning. He stated that: “If one person read the supplication for 40 mornings, will be considered and accounted as helpers of Imam Mahdi and if he (she) dies before the reappearance of Muhammad al-Mahdi, Allah will raise him (her) up from the grave.”
One of the sentences of this supplication is: “O Allah! If there occurs between me and his death, which you have decreed for your servants, then raise me from my grave, wrapped in my shroud, my sword unsheathed, my spear bared, answering the call of the caller in the cities as well as the deserts.”
In the prayer, the Shia supplicate to Allah that they see the Imam Mahdi in their life be and considering his helpers. Also, they supplicate to Allah to solve the problems of their nation and world with reappearance of Mahdi. In the end of supplication, reciter say: “Hasten! Hasten! O my Master, O Master of the era.” This phrase refers to the acceleration in the reappearance of Imam Mahdi(ajtf).
Imam Khomeini and Dua-e Ahad
When Ruhollah Khomeini was in hospital, he had a Mafatih al-Jinan book and recited Ahad prayer every morning. He wrote eight Shawwal on the corner of one page in the Mafatih. 8th Shawwal (20 days before his death) was the date of start for reciting Ahad supplication in period of 40 days. Imam said: "The person who reads this Dua every morning before the wishes and aspirations of Imam testament closes and the treaty with Muhammad al-Mahdi will swear allegiance to the death, faithful. Read this Dua and to emphasize is that this covenant between us and Muhammad al-Mahdi, is permanent and never will be weak and short."