Kabbalah su Salmi 89:31

They especially want to cleave to an area where there was once holiness that left. You can testify this in the Zohar in Vayechi (verse 197) regarding the departure of man that they want to cleave there because that is where holiness dwelled. For this reason my teacher would say that one who acts in ways of seclusion and purity and then leaves that holiness, they can defile him because of the aforementioned reason that they chase after places that once had holiness. I add another depth to this that the Klippot are called ‘nothingness’ and ‘emptiness’, and they only chase after things that are empty like them, and since they find a vessel that was emptied out from the holiness they cleave to it; and specifically about what it says in the Zohar in Mishpatim (verse 327): “All these Chariots and its companions always desire the thigh and yearn for it. As a result the knees of the sages are weary from THE OTHER SIDE, as all its yearning is for the thigh, and particularly for the sage’s thigh.” Therefore, sages (Talmidei Chachamim) need an even bigger caution since these run to cleave to them, and any side they find to cleave to they immediately cleave there and defile them. About this is said “If his sons forsake My law And do not walk according to My rules, If they violate My statutes And do not keep My commandments, then I will punish their transgression with the rod And their iniquity with strokes” (Psalms 89:31-33); “with strokes” means the plagues of men that are created by the Keri. Thus it is explained that when the holiness leaves, immediately one is repaid by these afflictions (Keri emissions).

Another reason for Keri is the pleasure of sleeping all night, as I said in chapter 5, and this is included in “If his sons forsake My law” (Psalms 89:31). And the reason for this is since he relinquished himself from dealing with Torah the Creator becomes his enemy, as it says “if you are slack in the day of trouble, how small is your strength” (Proverbs 24:10). This is measure for measure, since he did not want to connect with the “God fearing woman” [the Shechinah] via the study of Torah, he in turn connects to the External and foreign woman. He thus will bare demons to prosecute him and he will eat the fruit of his doings, since no evil comes down unless man cleaves to the Other Side, which makes the holiness leave, and then the Chitzonim have control over him since they are always ready and available. They are also called “Eleh” (these), as it says “since I do not have God in my midst these evil things befall me” (Deuteronomy 31:17). Therefore, when he awakes he should hasten to get up, since if he does not wake up and goes back to sleep he might sleep on his back facing up, which is cursed by the Scribes, as it says “Rabbi Yehoshua Ben Levi curses those who sleep on their back facing up” (Tractate Brachot 13b).