Whatsoever touches the altar shall be holy - To this our Lord refers Matthew 23:19, where he says the altar sanctifies the gift; and this may be understood as implying that whatever was laid on the altar became the Lord's property, and must be wholly devoted to sacred uses, for in no other sense could such things be sanctified by touching the altar.
The consecration of the priests. See the notes to Exodus 29:4
Door of the tabernacle - Entrance of the tent. See Leviticus 8:3.
The “waving” was the more solemn process of the two: it was a movement several times repeated, while “heaving” was simply a “lifting up” once.
A stranger - One of another family, i. e. in this case, one not of the family of Aaron.