Hadith: The Messenger of Allah (may Allah's peace and blessings be upon him) heard voices arguing at the door of his house.

عن أُمُّ سَلَمَة رضي الله عنها أن رسول الله صلى الله عليه وسلم سَمِعَ جَلَبَةَ خَصْمٍ بِبَابِ حُجْرَتِهِ، فَخَرَجَ إلَيْهِمْ، فقال: «ألا إنما أنا بشر، وإنما يأتيني الخصم، فلعل بعضكم أن يكون أبلغ من بعض؛ فَأَحْسِبُ أَنَّهُ صَادِقٌ؛ فَأَقْضِي لَهُ، فمن قضيت له بحق مسلم فإنما هي قطعة من نار، فَلْيَحْمِلْهَا أَوْ يَذَرْهَا».
[صحيح] - [متفق عليه]

Umm Salamah (may Allah be pleased with her) reported: The Messenger of Allah (may Allah's peace and blessings be upon him) heard voices arguing at the door of his house. He went out to them and said: "I am only a human being, and you refer your disputes to me. Perhaps some of you are more eloquent than others, so I deem him truthful and rule in his favor. He whom I, by my judgment, give an undue share of a Muslim's right, then it is indeed a portion of fire, so let him burden himself with it or abandon it."
[Authentic hadith] - [Narrated by Bukhari & Muslim]

Explanation

The Prophet (may Allah's peace and blessings be upon him) heard clamor at his door, due to people being engaged in dispute and quarrel. He went out to judge between them, saying: I am only a human like you. I do not know the unseen, nor am I informed about hidden matters so that I would recognize the truthful from the liar among you. People come to me to judge between them. My judgment, however, is based on each party's argument, evidence and oaths that I hear. Perhaps some are more eloquent than others and can express themselves better, so I believe them to be truthful and on the right side. Thus, I judge in their favor, although the truth, in reality, is on the other party's side. So, you should know that I give my judgment according to what is apparent and not what is hidden, which does not make the unlawful lawful. Consequently, whoever receives something based upon my judgment that is the right of his brother, while he knows that he is not taking it rightfully, then I am giving him nothing but a piece of fire. So, let him carry it, if he wishes, or leave it. The punishment for this returns upon him, and Allah is lying in wait for those who do injustice to others.