מוסר אויף איכה 3:2

I am now going to reveal to you a little bit but conceal twice as much regarding the concept behind the blue thread (techeiles) of the tzitzis: The value of the word ayin — “eye” — is 130, but since a man must gaze at his tzitzis with both eyes this comes to a total of 260. Add to this the numerical value of the word tzitzis, which is 590, and one receives a total of 850. This is exactly equal to the numerical value of the word techeiles. I have received an oral tradition from the illustrious Rabbi Yaakov Temerles of Lublin that a person should have this in mind while gazing at the tzitzis. Through this he helps eliminate the darkness intervening between us and the Shechinah, alluded to by the prophet Yirmiyahu in the verse, “You have led me into darkness and not light!” (Eichah 3:2). The main thing to recall is that the Holy One Blessed is He did not create the human being in this world for the benefit of his body, for the body is destined to disintegrate in the earth. Rather He created him for the benefit of his soul, which was carved out from beneath the Throne of Glory and is a portion of the Divine come down from On High. The soul was only brought here in order to rectify it and adorn it with good deeds that expedite the redemption and cause the Shechinah to rejoice in this bitter exile. Through this the soul refines the body as well, causing it to radiates with a clear light, especially when the body is “warmed up” by the performance of one of the mitzvos.