Narrated Anas:

The Prophet stayed for three days at a place between Khaibar and Medina, and there he consummated his marriage with Safiyya bint Huyay. I invited the Muslims to a banquet which included neither meat nor bread. The Prophet ordered for the leather dining sheets to be spread, and then dates, dried yogurt and butter were provided over it, and that was the Walima (banquet) of the Prophet. The Muslims asked whether Safiyya would be considered as his wife or as a slave girl of what his right hands possessed. Then they said, "If the Prophet screens her from the people, then she Is the Prophet's wife but if he does not screen her, then she is a slave girl." So when the Prophet proceeded, he made a place for her (on the camel) behind him and screened her from people.

حَدَّثَنَا مُحَمَّدُ بْنُ سَلاَمٍ، أَخْبَرَنَا إِسْمَاعِيلُ بْنُ جَعْفَرٍ، عَنْ حُمَيْدٍ، عَنْ أَنَسٍ، قَالَ أَقَامَ النَّبِيُّ ﷺ بَيْنَ خَيْبَرَ وَالْمَدِينَةِ ثَلاَثًا يُبْنَى عَلَيْهِ بِصَفِيَّةَ بِنْتِ حُيَىٍّ فَدَعَوْتُ الْمُسْلِمِينَ إِلَى وَلِيمَتِهِ، فَمَا كَانَ فِيهَا مِنْ خُبْزٍ وَلاَ لَحْمٍ، أَمَرَ بِالأَنْطَاعِ فَأُلْقِيَ فِيهَا مِنَ التَّمْرِ وَالأَقِطِ وَالسَّمْنِ فَكَانَتْ وَلِيمَتَهُ، فَقَالَ الْمُسْلِمُونَ إِحْدَى أُمَّهَاتِ الْمُؤْمِنِينَ أَوْ مِمَّا مَلَكَتْ يَمِينُهُ فَقَالُوا إِنْ حَجَبَهَا فَهْىَ مِنْ أُمَّهَاتِ الْمُؤْمِنِينَ، وَإِنْ لَمْ يَحْجُبْهَا فَهْىَ مِمَّا مَلَكَتْ يَمِينُهُ فَلَمَّا ارْتَحَلَ وَطَّى لَهَا خَلْفَهُ وَمَدَّ الْحِجَابَ بَيْنَهَا وَبَيْنَ النَّاسِ.