Sahih Bukhari | Volume 3 | Hadith Number 638

Narrated by Um Salama
(The wife of the Prophet) Allah's Apostle heard some people quarrelling at the door of his dwelling. He came out and said, "I am only a human being, and opponents come to me (to settle their problems); maybe someone amongst you can present his case more eloquently than the other, whereby I may consider him true and give a verdict in his favour. So, If I

give the right of a Muslim to another by mistake, then it is really a portion of (Hell) Fire, he has the option to take or give up (before the Day of Resurrection)."