Hadith: The Prophet (may Allah's peace and blessings be upon him) stayed for three nights between Khaybar and Madīnah when he married Safiyyah

عن أنس بن مالك رضي الله عنه قال: أقام النبي صلى الله عليه وسلم بين خيبر والمدينة ثلاث ليال يُبْنَى عليه بصفية، فدعوتُ المسلمين إلى وليمته، وما كان فيها من خبز ولا لحم، وما كان فيها إلا أن أمر بلالا بالأنْطَاعِ فَبُسِطَتْ، فألقى عليها التمر والأقِطَ والسَّمْنَ، فقال المسلمون: إحدى أمهات المؤمنين، أو ما مَلَكَتْ يمينه؟ قالوا: إن حَجَبَهَا فهي إحدى أمهات المؤمنين، وإن لم يحجبها فهي مما ملكت يمينه، فلما ارتحل وَطَّأَ لها خَلْفَهُ، ومَدَّ الحِجَابَ.
[صحيح] - [متفق عليه، وهذا لفظ البخاري]

Anas ibn Mālik (may Allah be pleased with him) reported: The Prophet (may Allah's peace and blessings be upon him) stayed for three nights between Khaybar and Madīnah when he married Safiyyah. I invited the Muslims to his wedding dinner and there was neither meat nor bread served in that dinner. Instead, the Prophet ordered Bilāl to spread out the leather mats and place dates, dried yogurt and butter on them. The Muslims asked: "Will she (i.e. Safiyyah) be one of the Mothers of the Believers (i.e. a wife of the Prophet), or just what his right-hand possesses (i.e. a concubine)?" Some of them said: "If the Prophet veils her, she will be one of the Mothers of the Believers, but if he doesn't, she will be his concubine." So when he departed, he prepared a place for her behind him and extended a screen around her.
[Authentic hadith] - [Al-Bukhari and Muslim. This is the wording of Al-Bukhari]

Explanation

The Prophet (may Allah's peace and blessings be upon him) traveled and stayed at a place between Khaybar and Madīnah for three days and three nights with the Mother of the Believers, Safiyyah (may Allah be pleased with her), when he married her. He arranged a wedding dinner and told Anas (may Allah be pleased with him) to invite people to eat. There was no meat or bread served at the dinner, due to the Prophet’s poor financial situation. So, mats were spread out and dates, dried yogurt, and the like were served. The people ate and wondered if Safiyyah had been taken as a wife or a concubine by the Prophet. Then they said: If the Prophet (may Allah's peace and blessings be upon him) screened Safiyyah, she would be one of the Mothers of the Believers, because veiling was obligatory upon them, but if he didn't, she would be a concubine. They were assured that she was a wife of the Prophet when he screened her and assigned a wide space for her behind him on his camel.