Chris said that the Levites would have starved to death if the Lord had not commanded the nation of Israel to give them tithes.
Apparently there was time during the days of Nehemiah in which the Levites were not given tithe. Fortunately the Levites we're not so lazy that they actually starved to death, but they had to abandon the work of the Temple.
Nehemiah 13:10-12 KJV And I perceived that the portions of the Levites had not been given them: for the Levites and the singers, that did the work, were fled every one to his field. Then contended I with the rulers, and said, Why is the house of God forsaken? And I gathered them together, and set them in their place. Then brought all Judah the tithe of the corn and the new wine and the oil unto the treasuries.