"Ibn 'Awn narrated to us, from Nafi', from Ibn 'Umar, from 'Umar, who said: 'I acquired some land at Khaibar. He came to the Prophet and said: I have acquired some land at Khaibar, and I have never been given any wealth that is more precious to me than it. What do you command me to do with it? He said: If you wish, you can 'freeze' it and give it in charity. So he gave it in charity on condition that it would not be sold, given away or inherited, to the poor, relatives, slaves, for the cause of Allah, guests and wayfarers. There is no sin on the one who administers it if he eats from it on a reasonable basis and feeds his friend, with no intention of becoming wealthy from it.'"
Sunan an-Nasa'i Book 29, Hadith 6
Barirah came to seek my help regarding her manumission (freedom). I told herself you like I would pay your price
to your masters but your Wala' (allegiance) would be for me." Her masters said, "If you like, you can
pay what remains (of the price of her manumission), (Sufyan the sub-narrator once said), or if you like
you can manumit her, but her (inheritance) Al-Wala would be for us. "When Allah's Messenger (ﷺ) came, I
spoke to him about it. He said, "Buy her and manumit her. No doubt Al-Wala' is for the manumitted."
Then Allah's Messenger (ﷺ) stood on the pulpit (or Allah's Messenger (ﷺ) ascended the pulpit as Sufyan once said),
and said, "What about some people who impose conditions which are not present in Allah's Book
(Laws)? Whoever imposes conditions which are not in Allah's Book (Laws), his conditions will be
invalid even if he imposed them a hundred times."
Sahih al-Bukhari Book 8, Hadith 104
A woman came to Allah's Messenger (ﷺ) and said, "I present myself (to you) (for marriage). She stayed for a
long while, then a man said, "If you are not in need of her then marry her to me." The Prophet (ﷺ) said,
"Have you got anything m order to pay her Mahr?" He said, "I have nothing with me except my Izar
(waist sheet)." The Prophet (ﷺ) said, "If you give her your Izar, you will have no Izar to wear, (so go) and
search for something. He said, "I could not find anything." The Prophet (ﷺ) said, "Try (to find something),
even if it were an iron ring But he was not able to find (even that) The Prophet (ﷺ) said (to him). "Do you
memorize something of the Quran?" "Yes. ' he said, "such Sura and such Sura," naming those Suras
The Prophet (ﷺ) said, "We have married her to you for what you know of the Quran (by heart).
Sahih al-Bukhari Book 67, Hadith 71