βασιλεία τῶν οὐρανῶν ἐντὸς ὑμῶν ἐστί. περὶ δὲ τὸν ἐντὸς ἄνθρωπον οὐδὲν ἕτερον ἢ θεωρία συνίσταται. θεωρία ἂν εἴη λοιπὸν ἡ βασιλεία τῶν οὐρανῶν. - Basil of Caesarea

I consider it absurd that we should permit our senses to sate themselves without hindrance with their own material food, but that we should exclude the mind alone from its own particular activity.

Such too was Moses, who rose up in great wrath to oppose those who sinned against God, but endured with meekness of spirit all slanders against himself.

Let one hour, the same regularly each day, be set aside for food, so that out of the twenty-four hours of day and night, barely shall this one be expended on the body, the ascetic devoting the remainder to the activities of the mind.