When will Hashem dispossess them?
Rashi: It will be after Yehoshua dies.
What is the reason for apportioning the land before it is conquered?
Rashi: Each Shevet will conquer what fell to it in the lottery.
Above (12:7), it is called Yerushah. Why is it called here Nachalah?
Malbim: Yerushah denotes emptying of jurisdiction. It goes out from this Reshus to another Reshus. Nachalah denotes bequeathing to children. Above it discussed what was conquered. It went from the Kena'anim's Reshus to Yisrael's. Nachalah did not apply, for that was before the lottery. It was not known who bequeaths and who inherits! Here, it was not conquered yet, so it cannot be called Yerushah. It was Nachalah
Where did Hashem command this?
Malbim: "Atah Tanchil Es ha'Am ha'Zeh" (1:6).