פירוש על קידושין 53:13

The baraita now compares money and deed with hazakah, the idea that one can acquire something by acting as its owner. A Hebrew slave can be acquired through money and deed but not by acting as a slave to someone. But hazakah is stronger because when acquiring multiple pieces of land from one person, a person can take possession of one and thereby acquire them all. When it comes to buying the land with money or deed, the money or deed must cover all of the pieces.