Meat-offerings were generally joined with the chief sacrifices. Offered it upon a rock; the angel's presence and command being a sufficient warrant for the offering of sacrifice by a person who was no priest, and in a place otherwise forbidden.
Related Commentaries of Judges 13:19
Judges 13:19
19 So Manoah took a kid with a meat offering, and offered it upon a rock unto the LORD: and the angel did wondrously; and Manoah and his wife looked on.