Sayyidah Umm Salamah (may Allah be pleased with her) said that the Messenger of Allah (peace and blessings be upon him) said: "I am only a human being, and you bring your disputes to me. Some of you may prevail over others in presenting their arguments, and I judge according to what I hear. If I judge in someone's favour concerning his brother's right, let him not take it, but let him understand that I am giving him a piece of Hellfire."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب آداب القاضي / 20502