How can al-Waqidi be an Imam in military campaigns (Maghazi) and biographies (Siyar), and his words be considered reliable therein, while he is deemed a liar in the science of Hadith? And what guarantees that he did not lie in military campaigns (Maghazi) and biographies (Siyar) as well?

A person's extensive knowledge and broad understanding do not necessarily qualify them as trustworthy in transmitting reports. This is why scholars criticized Al-Waqidi despite acknowledging his vast knowledge. He is considered abandoned (matruk) despite his extensive knowledge, and he would transmit distorted reports (maqloobat) from trustworthy narrators. Ahmad ibn Hanbal used to accuse him of lying. He was a leading authority in military expeditions (Maghazi) and biographies (Siyar), yet the texts of his reports are not preserved, and he is considered weak.

Therefore, Al-Waqidi's reports are not accepted until they are verified, whether in hadith science or in history. Books of Siyar and Maghazi are not free from weakness in many of their narrations, and Al-Waqidi's book is among them.

The prevailing characteristic of weakness in Siyar and Maghazi books generally is the reason why criticism of Al-Waqidi did not become prominent in these fields, unlike in hadith science, where his criticism became widespread and well-known.