Majma al-Zawaid — Hadith 7004

Sayyiduna Uqbah bin Amir al-Juhani (may Allah be pleased with him) narrates: I came to the Prophet (peace and blessings be upon him), and at that time two opposing parties were present before him who had brought a case. The Prophet (peace and blessings be upon him) said to me: "Judge between the two of them." I said: "May my father and mother be sacrificed for you, you are more entitled to this than I am." The Prophet (peace and blessings be upon him) said: "Judge between them." I said: "On what basis?" The Prophet (peace and blessings be upon him) said: "Exercise your reasoning (ijtihad). If you judge correctly, you will get ten good deeds, and if you do not judge correctly, you will get one good deed."
Al-Tabarani recorded it in al-Mu'jam al-Saghir and al-Mu'jam al-Awsat; its chain contains Hafs bin Sulayman al-Asadi, who is matruk (abandoned). It has already been mentioned before this that Ahmad recorded it with a chain whose narrators are the narrators of the Sahih.