Isaiah 58:4

(Vers. 4, 5.) Do not fast as you do to this day, to make your voice heard on high. Is this the kind of fast I have chosen, only a day for people to humble themselves? Is it only for bowing one's head like a reed and for lying in sackcloth and ashes? Is that what you call a fast, a day acceptable to the Lord? LXX: Why have we fasted,' they say, 'and you have not seen it? Why have we humbled ourselves, and you have not noticed?' And when you have bowed your neck like a circle, and have put sackcloth and ashes under you: do not call this an acceptable fast. He teaches not to reprove fasting itself which he had commanded, but how one should fast: moreover, before he teaches what they should follow, he instructs what they should avoid: That it may be heard, he says, in high places. Do not bring your clamor to prayer, praying in synagogues and corners of the streets, so that you may be seen by men (Matthew 6), and raise your voice on high, and with the Pharisee, who is condemned by the judgment of the Lord, proclaim your fasts and works (Luke 18). Because of these things, the Lord, reproving the prayer of the Pharisees, teaches the disciples how they should pray (Matthew 6). They should enter into the hidden chamber of their hearts, to speak to God alone, who can hear the silence of the heart; so that they may cry out in their hearts, 'Abba, Father' (Romans 8:15); and not make their faces disfigured, but wash with water and anoint their heads with oil. John the Evangelist also writes about this: 'And you have an anointing from the Holy One' (1 John 2:20): that by being anointed, they themselves may become holy. For God does not seek only affliction and humiliation of the soul through injury to the body, as if to twist the body in the manner of a circle and bow the neck, and to walk in sadness. According to what is said in the Psalms: I am afflicted and bowed down to the end; I was mournful all day long (Psalm 37:9). Nor does He seek for one to be clothed in sackcloth and sleep in ashes, as we read of David and Ahab (2 Samuel 3; 1 Kings 21); but that one should do these things along with those that follow. Moreover, the Apostle frequently says that he fasts (2 Corinthians 6 and 11), and the Lord, when he is taken away as a bridegroom from his disciples, teaches them to fast (Matthew 6). And in the Psalms, speaking of repentance, he says: I ate ashes like bread and…