This dua is meant to be recited after the recitation of Ziyarat of Ashura. In some books of supplication, this supplication is referred to as "Dua Alqamah" named after the companion of Imam Sadiq (a), Alqamah. However, Shaykh Abbas Qummi (qs) quotes very clear traditions in Mafatih al-Jinan that Imam Sadiq (a) recited this dua in the presence of the companion Safwan, not Alqamah. Therefore, the correct name of this supplication is "Dua to be recited after Ziyarat-e-Ashura" or "Dua Safwan".
This dua is meant to be recited after the recitation of Ziyarat of Ashura. In some books of supplication, this supplication is referred to as "Dua Alqamah" named after the companion of Imam Sadiq (a), Alqamah. However, Shaykh Abbas Qummi (qs) quotes very clear traditions in Mafatih al-Jinan that Imam Sadiq (a) recited this dua in the presence of the companion Safwan, not Alqamah. Therefore, the correct name of this supplication is "Dua to be recited after Ziyarat-e-Ashura" or "Dua Safwan".
Imam Saadiq (a.s) narrates that "one who recites this supplication for 40 mornings; he will be accounted amongst the helpers of Imam Mahdi (a.t.f.s). And if he happens to die before the reappearance of Imam Mahdi (a.t.f.s), Allah will raise him up from his rave so that he may assist the holy Imam (a.t.f.s).For every word that he recites in this supplication, Allah will grant him 1000 good deeds and will erase from his scroll of deeds 1000 sins".