Is it permissible for my father to buy and sell sheep in the same place where he bought them without moving them, knowing that the place is in the market and not owned by anyone?

It is not permissible to sell a purchased commodity before taking possession of it and moving it from its place, due to the saying of the Prophet (peace be upon him): "If you buy a sale, do not sell it until you take possession of it," and his saying: "He forbade selling goods where they are bought until merchants take possession of them and move them to their dwellings," and his saying: "Whoever buys food should not sell it until he takes full possession of it," and other items are similar to food. Taking possession of everything is according to its nature. Thus, moving animals, clothes, and similar items involves moving them from their place. If the purchase took place in a place not exclusive to the seller, such as a market, then possession is taken by moving the commodity to another place within the market or street.