Charles Ellicott Commentary Leviticus 6:27

"Whatsoever shall touch the flesh thereof shall be holy; and when there is sprinkled of the blood thereof upon any garment, thou shalt wash that whereon it was sprinkled in a holy place." — Leviticus 6:27 (ASV)

Whatsoever shall touch the flesh thereof. —Better, every one that toucheth the flesh thereof, as the Authorized Version rightly renders this phrase in Leviticus 6:18 of this very chapter, where it is explained.

And when there is sprinkled... —So peculiarly sacred was the sin offering that when any of its blood chanced to spurt upon the garment of the officiating priest, or the one who brought the sacrifice, the spot which received the stain had to be washed in the room of the court provided for this purpose.

This room contained a well which supplied the water for the sanctuary, thus preventing the blood from being profaned outside the holy place.

Thou shalt wash. —That is, Aaron, to whom the command was first given, and then his descendants, the priests, not the Israelite or layman.