Continuation of the explanation of the author's statement: "And that it must be possible to deliver it"

The Shaykh : It is built upon affection, love, and loyalty among Muslims. Thus, the evidence for making this condition a requirement is the Qur'an, the Sunnah, and sound reasoning. Then he derived from this his statement: "Therefore, the sale of a runaway slave, a stray animal, a bird in the air, a fish in the water, or usurped property from anyone other than the usurper or one capable of taking it is not valid". Yes, the reasoning is that what contains excessive uncertainty becomes a cause of enmity and hatred. In this case, if the buyer obtains the item, something arises in the seller's heart; and if he does not obtain it, something arises in the buyer's heart.
The author derived four issues or four scenarios from this, which will follow.