Umar bin Khattab got some land in Khaibar and he went to the Prophet ﷺ to consult him about it saying, "O Messenger of Allah ﷺ I got some land in Khaibar better than which I have never had, what do you suggest that I do with it?" The Prophet ﷺ said, "If you like you can give the land as endowment and give its fruits in charity." So ʿUmar gave it in charity as an endowment on the condition that would not be sold nor given to anybody as a present and not to be inherited, but its yield would be given in charity to the poor people, to the Kith and kin, for freeing slaves, for Allah's Cause, to the travelers and guests; and that there would be no harm if the guardian of the endowment ate from it according to his need with good intention, and fed others without storing it for the future." (Using translation from Bukhārī 2737)
أَصَابَ عُمَرُ ؓ أَرْضًا بِخَيْبَرَ فَأَتَى النَّبِيَّ ﷺ يَسْتَأْمِرُهُ فِيهَا فَقَالَ يَا رَسُولَ اللهِ إِنِّي أَصَبْتُ أَرْضًا بِخَيْبَرَ لَمْ أُصِبْ مَالًا قَطُّ هُوَ أَنْفَسُ عِنْدِي مِنْهُ فَمَا تَأْمُرُ بِهِ؟ فَقَالَ إِنْ شِئْتَ حَبَسْتَ أَصْلَهَا وَتَصَدَّقْتَ بِهَا قَالَ فَتَصَدَّقَ بِهَا عُمَرُ أَنْ لَا يُبَاعَ أَصْلُهَا وَلَا يُورَثَ وَلَا يُوهَبَ قَالَ فَتَصَدَّقَ عُمَرُ فِي الْفُقَرَاءِ وَفِي الْقُرْبَى وَالرِّقَابِ وَفِي سَبِيلِ اللهِ وَابْنِ السَّبِيلِ وَالضَّيْفِ لَا جُنَاحَ عَلَى مَنْ وَلِيَهَا أَنْ يَأْكُلَ مِنْهَا بِالْمَعْرُوفِ وَيُطْعِمَ صَدِيقًا غَيْرَ مُتَمَوِّلٍ فِيهِ قَالَ فَحَدَّثْتُ بِهَذَا الْحَدِيثِ مُحَمَّدًا فَلَمَّا بَلَغْتُ هَذَا الْمَكَانَ غَيْرَ مُتَمَوِّلٍ مَالًا قَالَ مُحَمَّدٌ غَيْرَ مُتَأَثِّلٍ مَالًا قَالَ ابْنُ عَوْنٍ وَأَخْبَرَنِي مَنْ قَرَأَ هَذَا الْكِتَابَ أَنَّ فِيهِ غَيْرَ مُتَأَثِّلٍ مَالًا