The ALD symbol is one of the 72 three-letter names of God, each with a different spiritual significance. If you've ever seen the movie Life of Pi, you'll remember that he was on a search for a code of 216 letters. That's 72x3, which are the total number of letters in all the names of God. The names derive from three versus in Exodus, each with exactly 72 letters, reformed and reorganized by exceedingly ancient tradition.