Bikkurim, Chapter One, Mishnah Two
Our mishnah brings scriptural support (meaning a midrash) for the rules found in the previous mishnah.
1) For what reason may he not bring them? Because it is said, The first-fruits of your land (Exodus 23:19)until all of their growth is on your land.
2) Sharecroppers, leasers, or occupiers of confiscated property (sikarikon), or a robber does not bring them for the same reason, because it says, The first-fruits of your land.
Section one: The Torah states that one brings first fruits from your land. Since in all of the cases in yesterdays mishnah a person used ground that did not belong to him for it was either public property or private property, in all of those cases he does not bring bikkurim.
Section two: The same verse explains why a person doesnt bring bikkurim if he doesnt own the land on which the fruit grew. Sharecroppers receive the land from its owner and in return they give him a percentage of the produce. Leasers give the owner a fixed sum, no matter what the level of produce is. An occupier refers to a person who bought land that the government had confiscated from its legal owners (see Gittin 5:6). Such a person does not own the property until he compensates the original owner. Since none of the people listed in this section own the land on which they have grown the fruit none of them bring bikkurim.