Counted, not summed: Exodus 14:19–21 gives three consecutive verses of seventy-two letters each, and written one above another and read boustrophedon they yield seventy-two three-letter sequences. The 72 is the count of the triads; the count of their letters is 216.
The seventy-two triads are the name the tradition calls the Shem ha-Meforash and the engine of a large part of later angelic magic: each triad, expanded with a divine suffix, gives one of the seventy-two angels of the corpus's shem_hamephorash table. Jewish Kabbalah reads the same triads primarily as divine names rather than as angels, and the difference between those two readings is one of the clearest fault lines between the Jewish and the Hermetic traditions.
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