Kabbalah zu Tehillim 147:1

The letter Nun entered and stood before Him saying, Master of the Universe, may it please You to create the world with me, because the phrase, "fearful in praises" [nora tehilot] (Ex. 15:11) starts with me. In the words of the righteous, "it is pleasant to sing glorious praise." (Ps. 147:1) ["praise" in Hebrew is nava] He said, Nun, go back to your place! It is because of you that the letter Samekh returned to its place. And you should depend on it for support. ["to fall" in Hebrew is nefilah, hence fall → support, nun → samekh] It immediately left His presence and returned to its place.