The Torah passage that forms the basis of this discussion explicitly names only four of the eleven spices — stacte, onycha, galbanum, and pure frankincense — and specifies that they are to be of equal measure (Shemot 30:34-38), yet oral tradition from Sinai requires all eleven; Valle, Inyanei HaKetores p. 3 explains that the Torah's explicit naming of only four suffices because the ketores functions, like the anointing oil, primarily to draw down the innermost divine attributes — Chokmah and Binah, Abba and Ima — and thereby to elevate the holy realms by purging external impurity, so that the four names convey the essential inward-directed purpose of the incense.
Building on this, Valle, Inyanei HaKetores p. 4 explains that the four spices are singled out by name because they are equal in weight and represent the connection between specific higher spiritual levels — crown, foundation, kingdom, and encompassing light — while the remaining seven are deliberately left unnamed so that the external forces cannot gain hold of them, since the incense's entire purpose is to nullify the vitality of those external forces.
Valle, Inyanei HaKetores p. 5 adds a further dimension: the four letters of God's specific Name shine within those four explicitly named spices, thereby rescuing the holy levels of creation from the grasp of external forces, and the act of pounding and mixing all the spices together — as a perfumer does — completes the bond of all holy levels and strengthens them against contamination.
On an allegorical plane, Valle, Inyanei HaKetores p. 15 interprets the four named spices as representing pillars of Torah study and spiritual perfection — myrrh for teachings flowing from the mouth, frankincense for freedom from subjugation, and the others for acquired wisdom, purity of heart, and sanctity — with the unnamed spices following implicitly from these foundations, so that the ketores as a whole symbolizes the spiritual reward of one who studies Torah in solitude and humility.
The broader structural logic underlying all of these explanations is clarified by Valle, Inyanei HaKetores p. 10, which holds that the incense altar functions as an extension radiating outward from the Ark at the heart of the Holy of Holies — binding all the holy grades together into a single unity — which is why the Torah itself introduces the ketores last among the sacred vessels, after all others are established and then unified through the incense offering.
