Shall take the hair of the head of his separation, and shall put it in the fire which is under the sacrifice of the peace offerings. It is not said, nor intended, that the hair was offered to God as a sacrifice.
If so, it would have been burnt with the burnt offering which represented the self-dedication of the worshipper. It had been holy to the Lord, growing uncut all the days of the vow. The vow was now at an end; the last solemn act of sacrifice, the peace offering, which completed all, and typified that fearless and thankful communion with God which is the end of all religion, was now going on; it was fitting that the hair which must now be shorn, but could not be disposed of in any ordinary way, should be burnt upon the altar of God.
In the fire, i.e; on the brazen altar. In later days it seems to have been done in a room assigned to the Nazirites in the court of the women: another deviation from the ordinal law.