The Levites a gift to Aaron

"As Aaron and his sons had the tribe of Levi placed at their disposal for the service of the tabernacle (Num. 8:19), so the mortal Levitical order are placed at the disposal of the Melchizedeck king-priest of the new constitution and his sons (for the brethren of Christ are also considered as his children—“I and the children which God hath given me.”) This is a feature made visible in “the ordinances of the house,” shewn to Ezekiel in vision."

1891 Christadelphian p6