Musannaf Ibn Abi Shaybah 24491 — What a judge should begin with

It is narrated from Abd al-Rahman bin Yazid that one day people pressed Sayyiduna Abdullah (may Allah be pleased with him) with many questions, and he said: "O people! A time has passed over us when we did not judge, nor were we present in the place of judgment. Then Allah Almighty placed the work of leadership in our destiny, as you see. So after today, whoever among you is faced with a case to judge should judge according to the Qur'an. If a matter comes up that is not in the Qur'an, he should judge according to the Sunnah of the Prophet (peace and blessings be upon him). If a matter comes up that is not in the Qur'an and hadith, then judge according to what the righteous have decided. And if there is a matter that is not in the Qur'an and Sunnah, and on which the righteous have not decided either, then exercise your own opinion, and let him not say: 'I think' and 'I fear.' Indeed, the lawful is clear and the unlawful is clear, and between them are some doubtful matters. So leave what puts you in doubt and take what is certain."