question #1 Sahih al-Bukhari 2775, Book 55, Hadith 38 : What is the ruling on taking back something that has been given in charity?

Once `Umar gave a horse in charity to be used in holy fighting. It had been given to him by Allah’s
Apostle . `Umar gave it to another man to ride. Then `Umar was informed that the man put the horse
for sale, so he asked Allah’s Messenger (ﷺ) whether he could buy it. Allah’s Messenger (ﷺ) replied, “You should not
buy it, for you should not take back what you have given in charity.”