I have seen some shias that use to quote these two authors and describe them as a prominent sunni scholars. But that’s a lie.
Sheikh `Âdil Sa`d Mabrûk, Researcher and Member of the Book Federation, said:
The author of this book is Ahmad b. Abî Ya`qûb Ishâq b. Ja`far b. Wahb b. Wâdih al-Ya`qûbî. He was a ward of Ibn Hishâm and a famous historian of the Imamite Shî`ah.
The date of his death was in the year 284 AH according to Yâqût. However, al-Zarkalî sets the date at 292 AH.
Al-Ya`qûbî was a widely traveled geographer who made extensive explorations of the Islamic lands of his time.
His History is divided into two parts. The first part deals with ancient history, including topics like the creation of the Earth, the story of Adam and his progeny, the flood, and the early Prophets. This part relies heavily on Jewish and Christian sources – he quotes liberally from the Torah and the New Testament – as well as folktales and legends. He speaks at particular length on their differing opinions regarding the date of Christ’s birth.
Interestingly, he eschews the Qur’ân and Sunnah as a source of information on all of these matters, though for a Muslim, these would be the sources that are free of doubt and inaccuracy regarding the Prophets of old.
The second part of his History begins from the birth of Prophet Muhammad (peace be upon him). Al-Ya`qûbî gives a brief account of his life the military campaigns of his time.
He goes on to give an account of all the important historical events that took place during the life of each Caliph. In fact, the book is organized by Caliph.
Al-Ya`qûbî mentions his sources for this part of his book. They consist exclusively of eleven historical narrators and two astrologers.
When he gets to his times, he relies on firsthand contemporary accounts. Only some of these witnesses he mentions by name.
The book presents the history of the Islamic polity from an Imamite Shî`ah perspective. Al-Ya`qûbî, therefore, does not recognize the legitimacy of any Caliph aside from `Alî b. Abî Tâlib and his children according to the order of succession set forth by his sect.
In fact, when he discusses the reigns of Abû Bakr, `Umar, and `Uthmân, he does not even refer to them as Caliphs. He simply says: “He assumed the political post…”
Moreover, he does not spare them, or any of the other Companions, his harsh criticism and condemnation. He relates especially slanderous things about `Â’ishah, kHâlid b. al-Walîd, `Amr b. al-`Âs, and Mu`âwiyah b. Abî Sufyân.
His account of how the Muslims first appointed the Caliph is full of accusations and inaccuracies. He essentially presents it as a conspiracy against the ascension of `Alî to the post. This is, of course, because of al-Ya`qûbî’s ideological and theological belief that `Alî was the divinely appointed inheritor of the Prophet (peace be upon him).
Because of the negative light in which al-Ya`qûbî depicts the Companions and the early events of Muslim history, his History has been relied upon heavily by orientalists.
However, its value as a historical sourcework is almost negligible. As for the first part of the book, it merely quotes the Bible and then embroiders the narrative with folktales and fables. A scholar who studies folk narratives might find some use in it.
As for the second half of the book, its historicity is colored by its extreme sectarian and ideological bias. It also lacks even a basic level of scholarly standards with respect to the reliability and verification of its sources.
About another one, al-Masoode, Allama al-Hilli in his “Khulasat” p 186 said:
علي بن الحسين بن علي المسعودي أبو الحسن الهذلي له كتب في الإمامة وغيرها منها كتاب في إثبات الوصية لعلي بن أبي طالب (ع) وهو صاحب كتاب مروج الذهب
“Ali ibn Hussain ibn Ali al-Masoode Abul Hasan al-Khuzali. He has a book about imamate and others, from them book in the proof of wasiyat to Ali ibn Abe Taleb (a) and he’s author of book “Muruj az-zahab”.
Almost the same info gave ibn Dawud al-Hilli in his “Rijal” p 137:
علي بن الحسين بن علي : المسعودي أبو الحسن لم له كتاب ” إثبات الوصية لعلي ع وهو صاحب ” مروج الذهب ” .
So no one shouldn’t be deceive when shias cite book “Muruj az-zahab” as a proof.