Wash you, make yourself clean; put away the evil of your doings from before my eyes; cease to do evil;
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Augustine of Hippo
AD 430
He [the one who is fasting] will wash his face, that is, cleanse his heart, with which he will see God, no veil being interposed on account of the infirmity contracted from squalor; but being firm and steadfast, inasmuch as he is pure and guileless.… From the squalor, therefore, by which the eye of God is offended, our face is to be washed.