One of the most important duties which the Shia must shoulder and undertake during the period of occultation is pray to Allah to hasten the reappearance of Imam Mahdi as well as for his wellbeing and safety.  There is no doubt that one can pray to Allah in any way he can, no matter what the language of prayer and supplication since it is listened and accepted by Allah.  What is important is the spirit of the supplication and the conditions which the supplications must meet.
Meanwhile, it goes without saying that the reported supplications which have been transmitted on the tongue of the Holy Ahlulbayt (family of the Prophet (S)) has double value. One of those supplications is the well-known dua which has been reported in different Shia sources and which is recited for wellbeing of Imam of Time (atf).
a) In his al-Kafi, Kulayni narrates this dua from Muhammad bin Isa and he narrates it from the nobles (i.e. the infallible Imams without providing a specific name).[1]
It seems that there are other narrators between Kulayni and Muhammad bin Isa bin ‘Ubaid who have been omitted from the chain of transmission due to the existence of a context[2] i.e. Ahmad bin Muhammad ‘Asemi, Ali bin Hasan bin Ali bin Fazzāl.
Kulayni has narrated this dua for the twenty third night of the month of Ramadhan. However, he has said that reciting this dua is good in the entire month of Ramadhan as well as on any given days, weeks and months of the year. [3]
b) In his Iqbal al-A’mal, Sayyid bin Tavus narrates this dua from a group of his companions including Ibn Abi Qarrah, and he narrates it on the authority of Ali bin Hasan bin Ali bin Fazzāl and he from Muhammad bin Isa bin ‘Ubaid and he also narrates it on his own authority from the Infallibles (AS).[4]
He has also narrated this dua for the twenty third night of the month of Ramadhan and then says that it is appropriate to recite it in all the months of the year.
c) Kaf’ami has narrated this dua in al-Mesbah[5] and al-Balad al-Amin[6] without providing any chain of transmission.
d) Kaf’ami narrates this dua in a disconnected (mursal) way in al-Balad al-Amin under Du’a Kanzul Arsh.[7]
Keeping into account these reports, we come to the conclusion that the first two reports are authentic.  As for the second two reports, in spite of the fact that the said dua has been reported as part of a long dua, we must say that, even if the chain of transmission has not been mentioned, the credit and trustworthiness of the narrator can be effective making us rely on the narration.
This dua has been reported differently in the textual sources or in the books of dua and the one which is rampant among Shia Muslims.  Some of the differences are as follows:
In some sources such as Al-Kafi, the dua begins with words like these:  Allahumma kun li walliyik fulan bin fulan «اللَّهُمَّ کُنْ لِوَلِیِّکَ فُلَانِ بْنِ فُلَانٍ»[8].  Although in this text, the name of Imam of Time (atf) has not been mentioned explicitly, given the text and chain of transmission of this dua, it is very certain that the terms ‘fulan bin fulan’ (he son of so and so) refer to him and now it is stated with the words “al-Hujjat ibn al-Hasan”.
Likewise, Kaf’ami and Sayyid bin Tavus have replaced the said ambiguous words as such:

«اللَّهُمَّ کُنْ لِوَلِیِّکَ الْقَائِمِ بِأَمْرِکَ الْحُجَّةِ مُحَمَّدِ بْنِ الْحَسَنِ الْمَهْدِی»[9]

“Allahumma kun li waliyyik al-qaim bi amrika al-Hujjah Muhammad bin al-Hasan al-Mahdi”

«اللَّهُمَّ کُنْ لِوَلِیِّکَ مُحَمَّدِ بْنِ الْحَسَنِ الْمَهْدِی»[10]

“Allahumma kun li waliyyik Muhammad bin al-Hasan al-Mahdi”
There is also another difference in Kulayni’s narration of the supplication. For instance, there is the word “wa ‘awna” before the word “wa ‘ainaa”. Also, the words “wa qāeda” have been placed in the supplication differently which indicates variation in the two versions of the supplication. However, the discrepancy does not have any impact on the meaning.
A Brief Explanation of the Dua for Wellbeing of Imam of Time (atf)
Generally speaking, the different parts of this dua indicate the truth and sincere faith of Shia Muslims who eagerly anticipate the coming and reappearance of their much awaited and loved Imam.
In this section, we translate and explain this dua in accordance with the most well-known version:
1.  Here is how it begins:

«اللَّهُمَّ کُنْ لِوَلِیِّک ‏َ الْحُجَّةِ بن الحَسَن ـ صَلَواتُک علیه و علی آبائه ـ فی هذه السّاعَةِ و فی کُلّ ساعَة».

The word “hujjat” in religious literature including the Holy Quran[11] has been used in a particular sense which is something with which Allah, the Exalted, argues with His servants affirming his rewards and punishments on the basis of those arguments.[12]
“Hujjat (proof), son of Al­-Hassan” in the supplication makes reference to the fact that Hazrat Mahdi (atf) son of Imam Hasan al-Askari (AS) is the last of divine authorities among His servants.
Therefore, the translation of this part of the supplication is as such:
“O Allah, be, for Your representative, the Hujjat (proof), son of Al­-Hassan, Your blessings be on him and his forefathers, in this hour and in every hour.”
2.  The term “waliyan” in Arabic means guardian and master. Sometimes, it means friends as opposed to enemy. In some cases, it has been used in the sense of ‘helper’[13] and one of the divine names is “waliyul momeneen”.[14] In any case, the point that is common between all the said meanings is helping, guardianship and managing the affairs. Hence, this passage means: ‘O Allah, be a guardian, and a helper of the Imam’.
3. The term “hāfizan” means to be a protector which is very clear.  That is to say, “O Allah, be a protector of the Imam against worldly and heavenly dangers and any harms.’
4. The term “qaedan” means leader and guide.[15] Here in this supplication, it means ‘O Lord, You be his guide and leader.’
5. The term “nāsira” derives from ‘nasr’ which means help and assistance.[16] In some sources, the term ‘awnā has been used which gives the same meaning.[17] Both of them mean ‘O Allah, be the helper of the noble Imam.’
6. Then there are the terms “wa dalilan wa ‘ayna”.  Here in this supplication, the term “dalil” means ‘proof’, ‘guide’ or someone who leads[18], and it refers to God, the Exalted, Who guides graciously all human beings in general and His noble servants in particular.  The complete and perfect meaning of guidance is in the words wa ‘ayna which mean ‘O Allah, be a helper and an eye.’
7. The sentence “hatta tuskinahu arzaka taw’aa”  means ‘until You make him live on the earth, in obedience to You’ and this is the wish of someone who anticipates the coming of the awaited Imam. The word taw’aa in this sentence could possibly have been used in the sense of obedience and adherence[19] which in this case refers to one’s belief to the effect that the Imam will reappear in compliance with Allah’s order and at His behest. Therefore, the sentence here means: ‘O Allah, make him live on the earth, in obedience (to You).’ It is likely that the word taw’a might mean acting heartily and of free choice[20] which in this case could have two possible meanings:
a) ‘O Lord, make him live on the earth while he is with all his heart surrendering to you and acting in submission to your will.’
b) ‘Make him live on the earth as he is willed by You to be on the earth.’
Finally, it is also possible that taw’a might derive from the word tatawwu’ which means to volunteer oneself to do certain actions.[21] In that case, the sentence would mean: ‘O Allah, make him live on the earth out of Your grace and blessing and by way of completing Your bounties on your servants.”
8.  The words “wa tumatti’ahu fiha tawilaa” refer to an aspiration on the part of those who want the Imam’s government to last for a long time. It means: ‘O Allah, cause him to live in it for a long time.”
As well, it can be said that this sentence may also mean the globalization of Imam Mahdi’s government, may Allah hasten his reappearance.[22]

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