This week’s Torah reading ends with the law of “fringes” or “tassels” (tzitzit). In pre-modern times, weavers used different means to finish off a piece of cloth so that it would not unravel. One way was to hem the cloth; another was to take the threads protruding from the end of the garment (technically, the warp threads) and group them together into bunches of ornamental tassels. In Num 15:38-40, Israelites are commanded to make such tassels on the corners of their garments, and to include in the tassels a special, tekhelet-colored thread.
In biblical times, the color tekhelet (probably a kind of violet or bluish purple) was manufactured from a certain snail that was then common along the eastern Mediterranean coastline. (This particular variety of snail had long been held to be extinct, though some now claim it has been rediscovered.) The manufacturing process employed to make the tekhelet dye was time-consuming and costly; scholars have calculated that it took something like 12,000 snails to made 1.4 grams of dye. Only the very wealthy could afford a whole garment of tekhelet; perhaps for this reason people sometimes speak of the color as “royal blue.” When, in the book of Esther, the king rewards the virtuous Mordechai, the latter walks out of the palace “in royal robes of tekhelet and white.”
In this week’s reading, the Torah first commands Israelites to make the tzitzit in Numbers 15:38; then the next verse says: “And it will be a tzitzit for you [in the plural], so that when you see it you will remember all of the commandments of the Lord and do them.”
This verse raises has two little questions: 1) why tell people that “it will be a tzitzit for you” when that was just mentioned in the previous verse—of course it will be a tzitzit! And 2) why should the sight of the tekhelet thread cause people to remember “all of the commandments of the Lord”? That color was certainly associated with kings and the very wealthy, but what did it have to do with remembering God’s commandments?
Actually, both questions are pretty easily answered. As to the first: the word tzitzit sounds as if it might be related to the verb hetzitz, “glance at, glimpse.” (The two words aren’t really related, but they sound as if they might be.) So the Torah seems to be saying: it’s called a tzitzit because you all are supposed to catch sight of it.
As for why catching sight of the tekhelet should remind people to “remember all of the commandments of the Lord,” this has nothing to do with royalty or the very rich, but with another major consumer of tekhelet, the great temple in Jerusalem. Anyone who visited the temple was immediately struck by the festival of colors that met the eye—including, prominently, tekhelet.
Thus, the anonymous author of the Letter of Aristeas describes “all the glorious vestments,” including the tassels “of marvelous colors.” Seeing it, he said, “a man would think he had come out of this world into another.” Ben Sira, a Jewish sage of the early second century BCE, similarly remarked on the “holy garment of gold and tekhelet and purple” with which God had adorned the priesthood—“How glorious was he [the high priest] … when he donned his glorious vestments and put on his garments of splendor.” In fact, for Philo of Alexandria and others, the priestly garments “would seem to be a likeness and copy of the universe.”
No wonder, then, that a glimpse of a single thread of tekhelet would bring to an ancient Israelite’s mind the splendor of the holiest place on earth, and that glimpse would cause him to come to his senses and remember all the commandments of the Torah.