*Minor differences ignored. Grouped by changes, with first version listed as example.
From thirty years old and upward,.... The Septuagint version here, and in Numbers 4:3, renders it, from twenty five years old and upward, agreeable to Numbers 8:24, at the which age the Levites went into the tabernacle, to wait and to learn their business, but they did not enter upon it till thirty:
even unto fifty years old shalt thou number them; at which age they were discharged from business:
everyone that entereth into the service, to do the work of the tabernacle of the congregation; See Gill on Numbers 4:3.
*More commentary available at chapter level.