'Join' in the Bible

"This is what pertains to the Levites: At the age of twenty-five years and upward one may begin to join the company in the work of the tent of meeting,

But also bring your relatives with you from the tribe of Levi, your ancestral tribe, so they may join you and assist you and your sons in front of the tent of the testimony.

They are to join you and guard the tent of meeting, doing all the work at the tent, but no unauthorized person may come near you.