holy anointing oil was an integral part of the ordination of the priesthood. The primary purpose of anointing with it was to set the anointed person or object apart as qodesh, or “holy” (Exodus 30:29).
Originally, the oil was used exclusively for the priests and the Tabernacle articles, but its use was later extended to include kings. It was forbidden to be used on an outsider or to be used on the body of any common person and the Israelites were forbidden to duplicate any like it for themselves (Ex. 30:32b).
Some segments of Christianity have continued the practice of using holy anointing oil as a devotional practice, as well as in various liturgies.