The Midrash in Bemidbar Rabba (18:1) notes the juxtaposition of the Parsha of Tzitzit and the beginning of Parshat Korach by suggesting the following as Korach’s challenge to Moshe’s position of authority: does a Talit that is completely woven with threads of תכלת require Tzitzit? What is the significance of the Mitzva of Tzitzit that out of all the Mitzvot, only this Mitzva was chosen by Korach as a challenge to Moshe’s authority?
R’ Yechiel Reuven Mendlebaum in his work דודאי ראובן explains as follows: The Rambam in מורה נבוכין divides Mitzvot into 2 basic categories: the first category is called דעות, those Mitzvot that increase our awareness of Hashem and our acceptance of His domain over all of creation. These Mitzvot include Shabbat, Shemittah, avoiding idol worship, etc. The second category of Mitzvot is מדות, those Mitzvot that establish within the Jewish people values that will allow for society to function properly. These Mitzvot include ערות, גזל, שפיכות דמים, etc.
Each of the two colors in the Tzitzit represents one of these categories. The blue color of the תכלת, which, according to the Gemara in Menachot reminds us of the כסא הכבוד, represents the first category of Mitzvot those that increase our awareness that there is a God who is Almighty, דעות. The white color represents the Mitzvot whose directive is to cleanse a person from his evil traits and to inculcate with him desire to do what is moral, מדות. When we look at the Tzitzit we will “Remember all the Mitzvot of Hashem” (Bemidbar Sinai 15:39), both the דעות and the מדות.
Therefore, Korach therefore approached Moshe with the following challenge: if Hashem provided the Jewish people with both דעות and מדות then there is no need for a leader. If each Jew performs the category of Mitzvot that provides him with the proper אמונה and also performs the מדות category, which allows for society to function smoothly then there should be no need for anyone to assume a position of authority. The fact that Moshe has assumed leadership is an indication that without him society would not follow the Mitzvot of the category if מדות (white) even if we already have a complete set of (תכלת) דעות.