The Search for an Ancient Blue

In the Book of Numbers, it is written that God said to Moses: “Speak to the sons of Israel, and tell them that they shall make for themselves tassels on the corners of their garments throughout their generations, and that they shall put on the tassel of each corner a cord of blue.” Yet it is comparatively rare to see Jews wearing prayer shawls with blue thread added to the fringes. Why this intransigence? The short answer is that it’s an extraordinarily difficult commandment to fulfill, and one...