Sayyiduna Abu Hurairah (may Allah be pleased with him) narrates that the Prophet Muhammad (peace and blessings be upon him) said: "When a judge makes a decision by exerting effort (ijtihad) and is correct, he receives two rewards, and when he makes a decision by exerting effort and makes a mistake, he receives one reward."

(Imam Ibn Hibban, may Allah have mercy on him, says:) Mu'ammar has narrated this same narration from Thawri as a musnad narration.