Before answering this question, explaining some hadithic terms is necessary:

A) Mutawatir Hadith:

Mutawatir literally means for things to come one after another, without any interval between them and in hadithic terms, refers to a hadith that has been narrated by a group of narrators that one can be definite haven’t all agreed on forging and lying about altogether. Any hadith with such a trait will surely make its reader certain that it is true. In other words, Shia scholars consider a hadith mutawatir, when the number of narrators in every level of its chain of narrators reach a degree in which causes complete satisfaction and certainty regarding its issuance from an infallible (as). This number isn’t a specific one; different factors may make it vary. The sole criterion is for the hadith to bring certainty and sureness that what it is conveying is what one of the infallibles has said. This is the common trait of all mutawatir hadiths, regardless of whether they are lafdhi, ma’nawi or ijmali ones.[1]

B) A mutawatir hadith is either lafdhi, ma’nawi or ijmali.

Lafdhi indicates that the mutawatir hadith is one that has been narrated many times with the same phrases and words. This kind of mutawatir hadith is very rare.

Ma’nawi signifies that a certain message is a common one amongst several hadiths. For instance, the courage of Imam Ali (as) is a mutawatir subject that different hadiths affirm.

Ijmali: When one knows that one of several hadiths on a certain topic has surely been issued from one of the infallibles, without knowing exactly which one.

Wahed: A hadith that has been narrated by one or several narrators which doesn’t cause anyone to be certain about the message it conveys, unless other signs are found that might help in trusting it.[2]

C) The classification of hadiths:

Hadith scholars have classified hadiths into four groups:

1- Sahih: A hadith with a complete chain of narrators from the final narrator to the imam, each narrator being reliable and of the Ithna Ashari sect and specifically confirmed as reliable in the rijali books (books that analyze the different narrators of hadiths).

2- Hasan: A hadith in which all of the narrators are of the Ithna Ashari sect and reliable, but haven’t been specifically confirmed in the rijali books.

3- Muwathaq: A hadith in which all of the narrators have been confirmed as reliable in rijali books, yet they all aren’t of the Ithna Ashari sect.

4- Dha’if or “weak”: Any hadith other than the three listed above.

D) Weak hadiths:

Hadith scholars have narrated weak hadiths in their books to be clues and evidence for the authenticity or unreliability of other hadiths, not to be used individually.

Taken into consideration all of the abovementioned facts, we will now begin to analyze the hadiths on the birth of Imam Zaman (as):

First of all: All of these hadiths aren’t weak ones and sahih, mowathaq and hasan ones can also be found in them[3]. Moreover, most of the narrators of the “weak” ones who might have been discredited in some books, have also been confirmed as reliable in others. Of course one might say that there is a rule that says when a narrator is both discredited and authorized in different books, he can no longer be relied on, but it isn’t an absolute rule without any exceptions. That is because sometimes a characteristic or anything else might be considered something that weakens the reliability of a narrator by a certain hadith scholar, while other scholars might not agree. Therefore, if a hadith scholar expresses why he believes that a certain narrator is a weak one, and others agree with him on it, his view will be acknowledged, otherwise not. So it is necessary for hadith scholars to say why they believe that a narrator is a weak one. In the introduction of his book, Lisanul-Mizan, Asqalani writes that this rule only applies to when the reason for a narrator’s weakness has been specifically mentioned, otherwise, it will no longer apply. So one can't say in an absolute manner that this rule is always applicable and whenever a narrator has been both discredited and confirmed, he can no longer be relied on.

Secondly, one must note that many of the hadiths that are considered weak ones today, used to be considered authentic ones according to past scholars. That is because they believed that any hadith they were sure had been issued by the imams was enough for the hadith to be an authentic one, without paying much attention to the chain of narrators. The terms listed above (sahih, muwathaq…) are all terms used for different hadiths without taking into consideration any of the other clues and evidence that might surround the hadith, making it a weak or authentic one even though according to the normal criteria for categorizing hadiths, it might fall under another category. The standards differ. Therefore, some of the hadiths on the birth of Imam Zaman (as) might be considered weak ones when analyzed with today’s hadith standards, while being authentic ones to those who might have also seen all of the evidence and clues outside of the hadith itself and its narrators, thus relying on the hadith. So one can't say that these hadiths are absolutely weak and there is no reason for relying on them.[4]

Thirdly, even in the case of most of the hadiths on the birth of Imam Zaman (as) being weak ones, since they are so high in number, they strengthen each other and altogether can make us certain about the common message they convey. In other words, both Shias and Sunnis have narrated many hadiths on the birth of Imam Zaman (as) and this issue is a clear one accepted by all. Of course, one can't claim that these hadiths reach the level of mutawatir lafdhi, but without a doubt, they do reach the level of mutawatir ma’nawi and one can certainly depend on them in what they are conveying (which is the birth of Imam Zaman (as)).

There are many historical and hadithic reasons for the birth of Imam Zaman (as); we will point to some historical documents:

1- Many famous Sunni scholars have accepted and written in their books that: The promised Mahdi (as) is the son of Imam Hasan Askari (as) and was born on the year 255 (ah) in the city of Samarra and is currently in occultation and will one day reappear by the will and order of Allah (swt).

2- Imam Hasan Askari (as) had foretold the birth of Imam Zaman (as). One of those who were informed of what was to take place, was Hakimah Khatun, the aunt of Imam Askari (as). He had told her that his son, Mahdi (as) was to be born on the fifteenth of the holy month of Sha’ban from his mother Narges Khatun.

Muhammad ibn Ali ibn Hamzah reports hearing Imam Askari (as) saying: “Allah’s (swt) proof to the people and the imam and my successor is to be born on the dawn of the fifteenth of Sha’ban.

In addition to the glad tidings that Imam Askari (as) had given regarding the birth of Imam Zaman (as), and him informing his close companions about the birth of his son, he also took another step and showed his son to some of his followers.

Ibrahim ibn Muhammad says: “I saw a beautiful child in the house of Imam Askari (as), I asked his excellency: “Oh son of Rasulullah! Who is this child? He replied: “This is my son. He is my successor.”

Despite the dangerous situation that Imam Askari (as) lived in, he showed his son to a great number of his reliable companions while informing another group of trustworthy individuals of his birth.

At the same time, he would insist on them not letting his enemies finding out about what had taken place.

After his glad tidings and showing his son to his close companions, he asked them to inform the Shias of the birth of Imam Mahdi (as) so that they would be freed of all doubt and worry.

Individuals such as Hakimah Khatun, Hasan ibn Husein Alawi, Hasan ibn Mundhir Mu’awiyyah ibn Hakim, Ali ibn Bilal, Ahmad ibn Hilal, Ahmad ibn Ishaq, Ali ibn Ibrahim Mahziyar and others all strived to inform the Shias of the birth of Imam Mahdi (as).

After the martyrdom of Imam Askari (as), Imam Mahdi (as) continued this mission by showing extraordinary things himself or through his representatives to prove the truth to the Shias.

Ishaq ibn Yaqub reports: “I heard Uthman ibn Sa’id (one of the four representatives of Imam Mahdi (as) during his minor occultation) saying: “A man from Iraq brought me some money to give to the imam (as). The imam (as) returned the money saying: “Your debt to your cousin (son of uncle from father’s side) is four hundred dirhams, pay it off using this money. The man was stunned and amazed. He thought and calculated further and reached the conclusion that he did indeed owe his cousin the four hundred dirhams. He cleared the debt and gave the rest of the money to the imam (as) and he accepted it.[5]

Furthermore, a great number of scholars whom no one doubts about their trustworthiness have seen the imam in different ways and have been at his service. Conclusion: Given all of the hadiths on the birth of Imam Zaman (as) and all of the clues and signs such as scholars and righteous people meeting with him, any unbiased person will become certain that Imam Mahdi (as) is amongst us today.

For further information, see: Question1369 ( ), index: Intellectual and Narrative reasoning on Imam Zaman (as) being alive.