The Prophet (ﷺ) said about Hamza's daughter, "I am not legally permitted to marry her, as foster relations are treated like blood relations (in marital affairs). She is the daughter of my foster brother."
Hilal bin Umaiya accused his wife before the Prophet (ﷺ) of committing illegal sexual intercourse with Sharik bin Sahma.' The Prophet (ﷺ) said, "Produce a proof, or else you would get the legal punishment (by being lashed) on your back." Hilal said, "O Allah's Messenger (ﷺ)! If anyone of us saw another man over his wife, would he go to search for a proof." The Prophet (ﷺ) went on saying, "Produce a proof or else you would get the legal…
Abu Sufyan told me that Heraclius said to him, "When I inquired you what he (i.e. Muhammad) ordered you, you replied that he ordered you to establish the prayer, to speak the truth, to be chaste, to keep promises and to pay back trusts." Then Heraclius added, "These are really the qualities of a prophet."