Why Biblical Blue (Techelet) ?
God commands the People of Israel:
"Hashem spoke to Moshe saying: Speak to the Children of Israel and say to them that they shall make themselves tzitzit on the corners of their garments throughout their generations. And they shall place upon the tzitzit of each corner a thread of Techelet... And you shall see it and remember all of the commandments of Hashem and you shall do them," Numbers 15:37-39
We are required to place a thread of blue on our tzitzit as a constant and conspicuous reminder of our stature as noble sons of the King of the Universe, always pursuing His mitzvot (commandments). What is the significance of this unique blue color known as Techelet?
"And the Rabbis said: Why does the Torah enjoin us regarding Techelet? Because Techelet resembles sapphire, and the Tablets were of sapphire, to tell you that so long as the people of Yisrael gaze upon this Techelet they are reminded of that which is inscribed on the Tablets and they fulfill it, and so it is written, 'And you shall see it and remember.' Mishnat Rabbi Eliezer, ch. 14
In ancient times purple and blue dyes derived from snails were so rare and sought after that they were literally worth their weight in gold. These precious dyes colored the robes of the kings and princes of Media, Babylon, Egypt, Greece and Rome. To wear them was to be identified with royalty.