"Speak to the Israelite people and instruct them to make for themselves fringes on the corners of their garments throughout the ages; let them attach a cord of blue to the fringe at each corner. That shall be your fringe; look at it and recall all the commandments of the Lord and observe them."
Numbers 15:38-9
The Hebrew Bible reads that Jews should wear the color blue, tekhelet, in their tallits. Historical evidence of what this color may have actually been is scarce and contradictory.
"According to tradition, its hue is blue—or better 'bluish'— however, interpreters of the Bible are radically diverse in their view as to how 'bluish' was tekhelet’s color. These divergent renditions range from green, turquoise, blue (light and dark), to dark blue-purple (or violet)." Koren, 2022
"Some omit the fact that Rashi consistently referred to the color of tekhelet as green (yarok). Conversely, some state that Rashi’s judgement was that tekhelet was the color of the dark skies at night." Koren, 2022
Professor and chemist Zvi C. Koren concludes that tekhelet would have been a dark bluish-purple.
"I'm blue do be, do be, do be do / I can't sleep at night for thinking of you / Every night about two / My love for you comes tumblin' down / I can't stand being here alone"
The Ikettes, "I'm Blue", 1961
Blue is sad! I think. People seem to think so. The lyrics of this song are sad and it's about being blue.
I don't think I can include quotes from every song with a sad lyricist writing about being blue. I love this song in Hairspray. Maybe blue's attitude depends on its beat.
"The deeper blue becomes, the more urgently it summons man toward the infinite, the more it arouses in him a longing for purity and, ultimately, for the supersensual."
Wassily Kandinsky, Concerning the Spiritual in Art, 1911