Son of man is Uranus, the higher octave of awareness working through the head, and the hair growing from that head is spiritual growth measured strand by strand. To shave it and weigh it on the balances is the intellect taking account of its own development, separating what has genuinely risen in a person from what has merely accumulated. The razor is discernment cutting close, and the scales are the deciding faculty that will not let growth go unexamined. The strange act is a witness in the body: energy that rose to the crown is gathered, divided, and judged by portions.
Son of man: Uranus, the higher mind expressing through the crown of the head.
Hair: spiritual growth, measured as it rises from the head.
Head: the seat of higher consciousness where the growth is gathered.
Balances: the weighing and deciding faculty of the intellect that judges what has grown.