Francis Blackburne in 1765 argued that John Jortin misread this and other passages from Luther, while Gottfried Fritschel pointed out in 1867 that it actually refers to the soul of a man "in this life" (homo enim in hac vita) tired from his daily labour (defatigus diurno labore) who at night enters his bedchamber (sub noctem intrat in cubiculum suum) and whose sleep is interrupted by dreams.
What did Fritschel say the man's sleep was disturbed by?
dreams