18 However, this perfect quiet is not the death of the mind but its true life. ". . . Instead of bringing darkness and lethargy, the sleep of the Spouse is wakeful and life-giving; it enlightens the mind, expels the death of sin, and bestows immortality. Nevertheless, it is indeed a sleep, which transports rather than stupefies the faculties. It is a true death. This I affirm without the least hesitation, since the Apostle says, in commendation of some who were still living in the flesh, 'You are dead, and your life is hid with Christ in God'."
Source: Doctor Mellifluus (Vatican.va)