And it shall be, when thou [art] come in unto the land
The land of Canaan, which they were now on the borders of, and just entering into:
which the Lord thy God giveth thee [for] an inheritance;
which is often mentioned, to observe that it was not through their merits, but his gift, that they should enjoy the land; and the rather here to enforce the following law concerning the basket of firstfruits:
and possessest it, and dwellest therein;
not only had entered into it, but got the possession of it, and settled there. This shows as Jarchi observes, that they were not bound to the firstfruits till they had subdued the land and divided it; not as soon as they were in it.