“The law of the field of possession is sometimes lenient and sometimes strict.”How so? Whether one dedicates a field in the sandy plain of Mahoz or in the orchards of Savaste, [if he would redeem it] he must pay fifty shekels of silver for [every part of the field sufficient for] the sowing of a homer of barley. But if it was a field which he bought, he must pay what it is worth. Rabbi Eliezer says: it is all the same whether it is a field of possession or one that he bought. What is the difference between the field of possession and one that he bought? A field of possession he must pay the [added] fifth, whereas for a field that he has bought he need not pay the added fifth.