Psalm 133:2 says, “כשׁמן הטוב על־הראשׁ ירד על־הזקן זקן־אהרן שׁירד על־פי מדותיו”
My question is this: Does שׁירד על־פי מדותיו (flows down over the collar of his robe) have reference to the שׁמן (oil/fat) or to הזקן (the beard)? Instinctively I’d assume that it is the oil that flows but it seems that this could be a reference to the beard. Or is it perhaps intentionally ambiguous in order to signify both? Hebrew experts, give me a hand with this, please.