(3) باب مَا جَاءَ فِي الْقَاضِي كَيْفَ يَقْضِي
Some men who were companions of Mu'adh narrated from Mu'adh that the Messenger of Allah (ﷺ) sent Mu'adh to Yemen, so he (ﷺ) said:
"How will you judge?" He said: "I will judge according to what is in Allah's Book." He said: "If it is not in Allah's Book ?" He said: "Then with the Sunnah of the Messenger of Allah (ﷺ)." He said: "If it is not in the Sunnah of Messenger of Allah (ﷺ)?" He said: "I will give in my view." He said: "All praise is due to Allah, the One Who made the messenger of the Messenger of Allah suitable."
Reference: Jami` at-Tirmidhi 1327
In-book reference: Book 15, Hadith 7
English translation: Vol. 3, Book 13, Hadith 1327