[It is] like the precious ointment upon the head
The composition which Moses was ordered to make of the principal spices, and therefore called precious; and which was poured on the heads of kings and priests, when they were anointed with it, ( Exodus 30:23-25 ) ;
that ran down upon the beard, [even] Aaron's beard;
this was put upon the head of Aaron when he was anointed, and so on any other high priest, and trickled down to his beard; see ( Exodus 29:7 ) . The reasons Kimchi and Ben Melech give, why the anointing of Aaron and other priests is mentioned, and not the anointing of a king, or of David himself, are, because the anointing of Aaron was first, and also more public and better known by the people;
that went down to the skirts of his garments;
or, "the mouth" or "opening of his garments" F1; not the extremity of them, as our version inclines to; for not so great a quantity of oil was poured upon him; nor would it have been decent to have his clothes thus greased from top to bottom: but the upper part of his garment, the top of the coat, on which the beard lay, as Jarchi; the neck or collar of it, as Kimchi and Ben Melech; the hole in which the head went through when it was put on, about which there was a band, that it might not be rent, ( Exodus 28:32 ) ( 39:23 ) ; where the Septuagint use the same word as here. Suidas
F1 (yp le) (epi thn wan) , Sept. "super os", Montanus, Piscator; "super os, vel aperturam", Michaelis; "in capitium", Tigurine version; "upon the collar of his garments", Ainsworth.
F2 In voce (wa) .