The foliage on the left are of tripartite form,the hair parting on John the Baptist head represent the pyramid or keystone, the staff appears to point to a skull which would represent John the Baptist getting his head cut off. It is the head that holds the pineal gland, which substitute for head of state head of church , as external sources instead of one's own head and process. the hand that is pointing is over the heart area which is really more central in the chest, with three fingers closed in on it again the triune nature.