The question is why wasn’t the world created by the letter Nun which is so good and beautiful? The letter “Nun” stands for 50, meaning “50 gates of Bina,” a whole correction, the breaking from the enslavement in Egypt, the receiving of the Torah. All this depends on the letter “Nun.” It matches the Sefira of Yesod of smallness with which we must work until the end of correction.
The Zivugim (couplings) are made in Yesod, which means in faith above reason, from the bottom up, until the end of correction. Apparently this letter is flawless and it rightly demands that the world be created by it and promises to bring it to the end of correction.
It’s all true, with one exception, this letter is powerless! If it weren’t for the letter “Samech” that can constantly count on smallness, Nun wouldn’t be able to do anything. So it’s impossible to perform corrections by this one attribute alone. The letter “Samech” must participate in every action in order to provide this support, the Light of Hassadim, and then, thanks to it, the attribute of Nun can operate in the Sefira of Yesod and not fall to Malchut. On the whole, all the letters are needed, and it’s impossible to bring the world to the desirable correction by that attribute, although the letter “Nun” actually has all it takes, except for its own power.
If you descend from Tifferet to Yesod, you are already in danger, since you begin to work with Malchut. This type of work is possible only from the bottom up, and so you need to keep yourself from falling and not starting to receive in the opposite direction: from the top down.
Who is helping you resist this temptation? There must be someone above to hold you by a rope, so that you will hold on to it and not fall. It’s as if I am being lowered into a well full of snakes and am held a bit above them, but very close.
It turns out that you are so close to Malchut, and you can rise and convey its fears and anxieties upward in order to sanctify them. But you totally depend on the rope you are suspended by; you totally depend on the upper, on the letter “Samech” that holds you.
From the 2nd part of the Daily Kabbalah Lesson 5/27/13, The Zohar