Sulaym bin Qays Helali Koofi is a well-known figure in the Islamic world, thanks mainly to his book. It has raised different controversies over the centuries and great scholars have discussed it. If its authenticity is proven, it can be referred to and cited to substantiate important issues such as disputed subjects among Shiite and Sunni Muslims.
However, the importance of this book does not imply that Sulaym has been an influential and famous individual in his era rather, based on his own reports in his book, he has been merely a reporter documenting what he saw and heard[1].
Our knowledge of Sulaym today is limited and there are no sufficient evidences and proofs about him. What has remained about him in rijal [containing biography and characteristics of narrators] and hadith collections is usually derived from his book and its prologue written by its narrators. According to its contents, Sulaym was born two years before hijra [Prophet's (PBUH) migration from Mecca to Medina] and arrived in Medina as a young man during Omar's caliphate. In this period, Sulaym concentrated his efforts on documenting and recording Saqifa and Fadak and their marginal events. He was Imam Ali's (PBUH) companion and an eye-witness of events. When the Commander of the Faithful, Ali (AS) was martyred and Umayya took over power, Sulaym was among Shiites who went into Umayya's black list[2].
The Importance of Sulaym's Book
The historical importance of this book can be studied from two viewpoints:
1-This book is the first hadith book ever written by Shiites surviving to date; so this precedence, if we acknowledge its attribution to Sulaym, increases its value and credibility to a great extent.
2-This book is very important since it provides reports about events following the holy Prophet's (PBUH) demise and Imam Ali's (PBUH) rule.  One of its prominent features is an account of events over which Shiite and Sunni Muslims always disputed. Holy Prophet's (PBUH) emphasis on the issue of imamat and wilayat, the issue of Fadak, attacking and setting Fatima's (PBUH) house on fire are among those events recorded in this book.
Different Views about the Authenticity of Sulaym's Book
From sixth century on Sulaym's book gains growing prominence and his traditions enter Shiite hadith collections with more details. In this period, books with more citations from Sulaym's book are al-Ehtejaj by Sheikh Tabarsi and then Ershad ul-Qulub by Deylami. It is approximately from this time that some of Sulaym's hadiths find their way into Sunni sources as well[3].
Viewpoints about this book can be generally divided into three groups:
1- First group including most of Shiite scholars and hadith narrators consider Sulaym's book as an authentic and well-documented source whose pioneer is Muhaddeth No'mani (early fourth century) who stipulates that all contents of Sulaym's book are authentic. Kashshi's words also indicate that he verifies Sulaym and his book. Although Sheikh Tousi and Najjashi mention their chain of narration up to Sulaym's book, there is no evidence in their words accepting or weakening this book. Recent hadith and rijal scholars have more confidence in the authenticity of this book and its contents[4].
2- Some have rejected this book; some reject its attribution to Sulaym stating it is in fact a forged book while some others acknowledge its attribution to Sulaym[5] but consider its traditions and hadith as unreliable[6].
3- Third theory tries to find a way in the middle. It acknowledges Sulaym's book and its authenticity and rejects evidences and reason by Ibn Gaza'eri for its forgery. They believe, on the other hand, that copies of this book remained from later centuries are not free of falsification. Thus, Sulaym's traditions should be dealt with carefully and narrated and published only after examination and investigation. This viewpoint has some advocates from recent scholars as well[7].  Based on this viewpoint, all traditions of Sulaym's book should be evaluated like other traditions and then be decided. Here we cite a tradition from Sulaym's book narrated in authentic books and acknowledged by scholars: "Imam Ali (PBUH) has quoted holy Prophet (PBUH) as saying:"Scholars fall in two categories; they either act upon their knowledge and they receive salvation or they do not act upon their knowledge and they perish." [8]
There are many similar traditions from Sulaym having been also mentioned in authentic books and it can be a supporting fact for the third viewpoint that each tradition should be evaluated separately and if it is reliable it will be accepted otherwise it will be rejected. This way it will be more likely to find the truth about Sulaym's hadiths.
Criticisms of His Book
As a rijal scholar, Ibn Ghaza'eri states about Sulaym's book:"This book is undoubtedly forged. There are evidences and proofs within the book itself. Following this claim, he mentions some instances to prove his point of view regarding the book[9]. Except Ghaza'eri who questions the authenticity of the book itself, there are other scholars who acknowledge the attribution of book to Sulaym, however, they question its traditions and criticize it.
Some of general criticisms about the book are the following:
1- Denotation and connotation of some of Sulaym's traditions existing today are sometimes equivocal and shaky and sometimes sturdy and incomplete, this sturdiness may be an indication of falsification and error in this book.
2- Little or no attention by some preceding Shiite scholars toward this book also raises questions about it. For example, throughout all his books and treatises, Seyyed Murtadha never mentions Sulaym's book and he has mentioned only a single short tradition from Sulaym in his entire works. Among other scholars not mentioning Sulaym's book, is Seyyed ibn Tavous. This is more surprising since Seyyed ibn Tavous and Seyyed Murtadha owned a famous and rich library and it seems to be almost impossible that Seyyed, with his strong interest in collecting books, has not been familiar with Sulaym's book. He has almost undoubtedly seen that book. Now imagine that Seyyed bin Tavous has not mentioned Sulaym's book and even those traditions that he has narrated from Sulaym are all from other books. In his book Kashf al-Muhajja, Seyyed bin Tavous repeatedly refers his son to ibn Helal Saqafi's book (al-Ma'refat fil Manaqeb wa al-Masa'eb) about Saqifa and following events without mentioning Sulaym's book. This questions his confidence in that book.
3- What great scholars of hadith have mentioned from Sulaym in different books do not comply with current contents of Sulaym's book so this is another issue that requires more study and investigation. With a glimpse it can be figured out that some subjects of the existing copies are not found in any tradition collections from early decades of Islam such as al-Kafi, Khesal, Man la Yahdhoroh al-Faqih and al-Estebsar[10].
However, there are many works mentioning minor errors about Sulaym's book following the hadith not mentioned here[11] due to the short nature of this answer.
 However, those who acknowledge this book have provided very detailed answers and through responding to these issues they have tried to prove its authenticity. Among the advocates is the translator of new edition of this book who has tried a lot to prove the authenticity of the traditions.
In new impression of the book extensive research has been conducted about its traditions. The translator and researcher of this book has tried to see different copies of this book and write the text based on those different copies. Moreover efforts have been made in the new edition that Sulaym's traditions narrated in other books be collected. Also, efforts have been made back up Sulaym's traditions by mentioning other sources that have brought up those traditions. 
 
 

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