All this is simple enough, but to find the ‘treasure’ for which we are searching we need to look deeper into these ancient walls. One might ask a rather legalistic question regarding these Canaanite treasures. When a Canaanite house was taken over by a new Jewish owner, did the treasure in the wall also automatically become the property of the Jew, or was it necessary for the Jew to actually find the treasure to become its legal owner? Let us explain.
According to Jewish monetary law, ownership of an object occurs when a legally recognized act of acquisition (a kinyan) is performed upon the object. Until a kinyan is made, ownership is not established. For instance, in order to actually become the owner of your grocery order that was delivered to your door, you must actually lift up the box or drag it into your house. It is technically not yours when it is initially placed in front of your house by the deliveryman. In our case, as soon as the new Israelite owner had taken possession of the Canaanite house, a certain halachically recognized kinyan, called kinyan chatzer, could potentially be made automatically upon the treasure. According to the Torah, a kinyan is considered to have been performed automatically upon an object when the object is located in the acquirer’s secured courtyard (chatzer) or property similar to the courtyard archetype (e.g., a house). The question at hand is as follows. Is a kinyan (in this case, kinyan chatzer) performed upon an object valid when the acquirer does not have reason to suspect that the object exists, or is a certain level of knowledge regarding the possibility of the object’s existence necessary in order to become its owner?
Let us make this question a little more tangible. What would happen if the owner of the house did not find the hidden Canaanite treasure, but, rather, a stranger found it by tapping on the walls of the house when the owner was away? Who would own the treasure, the owner of the house, or the treasure-hunting tapper? If the owner of the house can make an automatic kinyan chatzer on a treasure that he does not have reason to believe exists, then the treasure is his, but if he can’t, then the treasure belongs to the stranger.
This question should sound awfully familiar because it seems to be precisely the same question asked to the Bais Havaad by the man who had found the hundred dollar bill in the suit bought at the thrift shop. If the owner of the thrift shop is able to acquire the money through kinyan chatzer though he did not know about the money’s existence, then the money belongs to him. If not, then the money belongs to the man who purchased the suit.
In Bava Metziah 25b, the Talmud states that a person who finds an ancient treasure in the walls of someone else’s house can keep his find because he can presume that the treasure was put there by the Amori’im, one of the Canaanite tribes. The Mordechai, in Bava Metziah, siman 258, explains that the owner of the house does not acquire the treasure by means of kinyan chatzer because he had no idea that a treasure might be hidden in the walls of his house. This ruling of the Mordechai is codified in the glosses of the Remah on the Shulchan Aruch in Choshen Mishpat 232:18 and 268:3. Applying this ruling to our case, it would seem that the man who asked the question to the Bais HaVaad could keep the hundred dollars that he found. However, there is one more thing to consider.