Thou - shalt wash them - This was done emblematically, to signify that they were to put away all filthiness of the flesh and spirit, and perfect holiness in the fear of God; 2 Corinthians 7:1.
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.