There is a census taken of available soldiers in Numbers 1. The Levites were not numbered with them. Not only were they the “Priestly Tribe” with the priests coming from Aarons family, but they were the Tribe that was to take care of the Tabernacle.
EXCLUSIVE CARE – Vss. 47-51 – They were exempt from military service in order to serve God exclusively.
EXTREME CLOSENESS – Vss. 52-53 – They were to be camped as close to God’s presence as possible.
EXCELLENT PRIVILEGE – Vs. 53 – They were to guard the Tabernacle.