Many of the Levites who were called by God to work as priests and singers in the temple returned to their fields in order to survive. No longer were they available to do the Lord’s work. Enter Nehemiah:
“I also learned that the portions assigned to the Levites had not been given to them, and that all the Levites and singers responsible for the service had gone back to their own fields. So I rebuked the officials and asked them, “Why is the house of God neglected?” …All Judah brought the tithes of grain, new wine and oil into the storerooms.”
I can tell you that there would be a lot more folks on the mission field if this was understood.