The Prophet (PBUH) refused any ruling that contradicted Allah’s legislation

“Rule between us with Allah’s Book.” The other man, who had more understanding and was more knowledgeable, said: “Yes, O Messenger of Allah, rule between us with Allah’s Book, and allow me to speak.” The Messenger of Allah, sallallaahu ‘alayhi wa sallam, said: “Speak.” He said: “My son was an employee of this man, and he committed adultery with his wife, so I was told that he must be stoned. After that, I gave one-hundred sheep and a slave girl as a ransom for his sake. Afterwards, I asked the people of knowledge, and they told me that my son is to be lashed one hundred times, and is to be banished for one year, and that his wife must be stoned.” The Messenger of Allah, sallallaahu ‘alayhi wa sallam, then said: “By Him in Whose hand is my soul, I will rule between you with Allah’s Book. As for your sheep and slave girl, they are to be given back to you, and your son must be lashed one-hundred times and banished for a year. O Unais, go to the wife of this man, and ask her about this claim. If she admits to it, then stone her.” Unais went and asked her, and she admitted to it. Afterwards, the Messenger of Allah, sallallaahu ‘alayhi wa sallam, ordered that she be stoned, and she was.