The Torah, “Numbers,” 15:37 – 15:41: The Lord spoke to Moses, saying: Speak to the children of Israel and you shall say to them that they shall make for themselves fringes on the corners of their garments, throughout their generations, and they shall affix a thread of sky blue [wool] on the fringe of each corner. This shall be fringes for you, and when you see it, you will remember all the commandments of the Lord to perform them, and you shall not wander after your hearts and after your eyes after which you are going astray. So that you shall remember and perform all My commandments and you shall be holy to your God. I am the Lord, your God, Who took you out of the land of Egypt to be your God; I am the Lord, your God.
There have to be special fringes that are tied in a special way in all the four corners of every garment and every piece of clothing. These fringes symbolize the four parts of the spiritual vessel: Hochma, Bina, Zeir Anpin, and Malchut, which should all be corrected and added. This means that they are studied and absorbed by the help of 613 commandments, 613 desires a person has, so that he will always be aware of their correction.
A person covers himself with these clothes only during the day and it is called a “prayer shawl” because when he is in the Creator’s Light he has to constantly remember how to be adapted to the Light, to constantly yearn for it, and resemble it, but not at night.
The blanket with which we cover ourselves has to have fringes in its corners that have to be tied. If they are not tied, they have to be cut with scissors into one small end so that it can be rounded. All the corners of the rectangle (Hochma, Bina, Zeir Anpin, and Malchut) where the Parsa goes through from Malchut to Bina, symbolize the spiritual vessel that has to be fully adapted to the Creator’s attributes, which means to be totally corrected in all its 613 desires.
A person has to constantly see them before him as the place for his correction. Therefore the knots on his clothes remind him that he has to constantly be subordinate to them so that he will look at these fringes each time and think about his 613 desires. On the level of our world these are only physical actions, of course, while in the spiritual world they symbolize that a person is corrected. Being under the prayer shawl refers to a spiritual person.
From KabTV’s “Secrets of the Eternal Book” 5/13/15