An inquiry into the traditions reveals that the phrase “hasten his reappearance” or “may Allah hasten their reappearance” was added to salawat in the time of the Holy Prophet (S) and pure Imams (AS). Here are a few reports to mention:
1. In a supplication named “Dua-e Hariq”[1] reported by Imam Sadiq (AS) from the imams before him it has been stated that Gabriel descended upon the Prophet of Islam (S) and taught him this supplication[2] which reads partially as such: “…اللَّهُمَّ صَلِّ عَلَى مُحَمَّدٍ وَ أَهْلِ بَيْتِهِ الطَّيِّبِينَ وَ عَجِّلِ اللَّهُمَّ فَرَجَهُم …”[3] O Allah send blessings and benediction upon Muhammad and his pure household. O Allah, hasten their reappearance….
2. Imam Hussein (AS) narrates a supplication from Imam Ali (AS) part of which reads as such:

«الْحَمْدُ لِلَّهِ رَبِّ الْعالَمِينَ وَ صَلَّى اللَّهُ عَلَى طَيِّبِ الْمُرْسَلِين ... ‏صَلِّ عَلَى مُحَمَّدٍ وَ آلِ مُحَمَّدٍ وَ عَجِّلْ فَرَجَهُم‏...».[4]

Ishaq bin Ammar says, “I said to Imam Sadiq (AS) that I was afraid of scorpions. Imam (AS) after mentioning certain manners, said: “Say thrice: “«اللَّهُمَّ رَبَّ أَسْلَمَ‏ صَلِّ عَلَى مُحَمَّدٍ وَ آلِ مُحَمَّدٍ وَ عَجِّلْ‏ فَرَجَهُمْ‏...» [5]
4. In another tradition Imam Sadiq (AS) says: “Whoever says after Dawn and Midday prayers: «اللَّهُمَّ صَلِّ عَلَى مُحَمَّدٍ وَ آلِ مُحَمَّدٍ وَ عَجِّلْ‏ فَرَجَهُمْ‏»، He will not die except that he will live in the time of the reappearance of the Riser from the family of the Prophet (S). [6]
Amr bin Abi Meghdam says: “Imam Sadiq (AS) taught me a dua and said: “The good of the world and the hereafter are gathered in this dua. Part of the dua reads:

«اللَّهُمَّ صَلِّ عَلَى مُحَمَّدٍ وَ آلِ مُحَمَّدٍ وَ عَجِّلْ‏ فَرَجَهُمْ‏ وَ رُوحَهُمْ وَ رَاحَتَهُمْ وَ سُرُورَهُمْ وَ أَذِقْنِي طَعْمَ فَرَجِهِمْ وَ أَهْلِكْ أَعْدَاءَهُمْ مِنَ الْجِنِّ وَ الْإِنْس»[7]

The reason has been to appeal for getting rid of grief and sorrow and to ask for ease in the affairs of the AhlulBayt (AS).

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