Augustine of Hippo

(de Genesi ad Literam. xii. 26.) No one seeing God can be alive with the life men have on earth, or with these our bodily senses. Unless one die altogether out of this life, either by totally departing from the body, or so alienated from earnal lusts that he may truly say with the Apostle, whether in the body or out of the body, I cannot tell, he is not translated that he should see this vision.