In memory of Rabbi Levi Yitzchok ben R' Zalman Yuda Deitsch OBM
When the Land of Israel was originally divided amongst the tribes, the Levites - who served in the Holy Temple and were the teachers of Torah - did not receive a portion. This is because the material nature of the world prevents a person from being both totally dedicated to G-d and simultaneously involved with worldly affairs. In the Era of the Redemption, however, when the world will be refined there will be no need for the Levites to set themselves aside from worldly involvement. And hence, they too will receive a portion of the Land of Israel.
(The Lubavitcher Rebbe, 26 Sivan, 5751-1991)