All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad, sallallaahu 'alayhi wa sallam, is His slave and Messenger.
Dr. Ali As-Sallaabi penned a book on the Seerah (biography of the Prophet ), entitled: As-Seerah An-Nabawiyyah: ‘Ardh Waqaai’ wa Tahleel Ahdaath. He also wrote a book about the battles of the Prophet and authored a collection of books about the biographies of some Muslim figures, including the rightly-guided Caliphs.
These books, like all other books on biographies and Fadhaa’il Al-A‘maal (virtuous deeds and their rewards), are not free of Dha‘eef (inauthentic) Ahadeeth. The customary practice among most authors who wrote in such topics (biographies and Fadhaa’il Al-A‘maal) was to cite both authentic and inauthentic Ahaadeeth, and they were not strict in this regard. Imam Ahmad ibn Hanbal and other leading scholars said: “If we narrate Ahaadeeth on what is lawful and what is unlawful, we are strict (in verifying their authenticity), but if we narrate Ahaadeeth on Fadhaa’il Al-A‘maal and similar topics, we are not as strict.” [End of Quote]
Ibn Sayyid An-Naas said in ‘Uyoon Al-Athar: “Many scholars were less strict when narrating (Ahaadeeth and reports) on Ar-Raqaa’iq (heart-softening topics) and the topics that do not involve Sharee‘ah rulings, like reports about battles and whatever is in the same vein. They held that what may be acceptable in these topics is not accepted in topics addressing the lawfulness and unlawfulness of matters, because no Sharee‘ah rulings are attached to them…” [End of Quote]
Allah knows best.