According to Jewish law, transferring ownership of an object requires a kinyan – a symbolic act of possession – the most common of which is hagbaha, where the purchaser lifts an object up in the air. What types on kinyanim are used when the object is too heavy to lift, e.g. the boat that is discussed in our perek? Two candidates presented by the Gemara are:
- mesira (passing), where the owner hands the object over to the buyer and says “here it is, take possession of it,” and
- meshikha (pulling), where the purchaser pulls it a little bit, making it move.
The Ramban quotes Rav Hai Ga’on as explaining that the kinyan of mesira is the weakest of all kinyanim, and it is only through the proactive statement of the owner that the action has any significance. Our Gemara makes it clear that this kinyan works for a boat, and the Rambam extends its significance to other situations where the object is too heavy for other kinyanim to be used. The Rosh limits kinyan mesira to boats where a simple touch can move the entire boat when it is standing in water, an act that can be interpreted to indicate ownership. Others limit it to boats and animals; boats because they cannot really be carried onto dry land and animals because it is common practice for the owner to hold onto the animal so that it should not run away. According to the Ramah a kinyan mesira will work in all cases where the object is actually handed by the owner into the hands of the purchaser; all of the limitations apply only to cases where the purchaser takes hold of the object on his own.
Meshikha is a more powerful kinyan, since the purchaser causes the object that he is buying to move, which is understood to be a sign of ownership.