4. Muhammad ibn Yahya has narrated from Muhammad ibn al-Hassan who has narrated the following:

“I once wrote to abu Muhammad, Alayhi al-Salam, and asked about the case of a man who sells a piece of land to another man. He does not know its limits, and so he does not appoint any witness to the deal, saying that when the limits are defined then witnesses are appointed; if it is permissible to bear witness or not. He (the Imam), Alayhi al-Salam, signed the answer that said, ‘Yes, it is permissible, all praise belongs to Allah.’ A man wanted to leave for Makkah. He had certain pieces of land in a town, which was a certain distance away from his home. He did not define the limits of the land. He only knew the limits of the town, all of its four sides. He said to the witnesses to bear witness that he has sold the whole town of such and such limits of all four sides one, two, three and four, to so and so. In fact, he only owned a piece of land in the town; if buying as such is permissible, when he has confirmed for him the selling of the whole town. He (the Imam) signed the answer that said, ‘It is not permissible to sell what does not belong to him, however, the purchase of what he owns has become binding in favor of the buyer.’ A man wrote to him (the Imam) asking if it is permissible for the witnesses whom he had appointed to bear testimony for the selling of the whole town to testify about the limits of the land that he owns in the town. He may have come to know such limits of such land through the people of the town if they are just people. He (the Imam) signed the answer that said, ‘Yes, it is permissible about something which is known and understood.’ A man wrote saying that a man says to another man to bear witness that the whole of the house that he owns in such and such place with its limits, all of it is for so and so with all that is in the house of assets; if the buyer can have all that is in the house. He (the Imam), Alayhi al-Salam, signed the answer that said, ‘It is permissible for all that the buying has covered, by the will of Allah.’”