When deep sleep falleth upon men and they are sleeping in their beds, then He openeth the ears of men, and teaching, instructeth them in what they are to learn.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic learning sleep
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/17897/pg17897-images.html

Context

“But wisdom perfects the intellect which precedes the will; hence without any complete movement of the free-will, the intellect can be enlightened with the gift of wisdom, even as we see that things are revealed to men in sleep, according to Job 33:15, 16: "When deep sleep falleth upon men and they are sleeping in their beds, then He openeth the ears of men, and teaching, instructeth them in what they are to learn." Reply Obj. 3: In the infusion of justifying grace there is a certain transmutation of the human soul, and hence a proper movement of the human soul is required in order that the soul may be moved in its own manner.” source