Matthew 6:16-18

Precepts for private fasts (not in St. Luke). Our Lord says nothing of public fasts, because when every one else is fasting there is little temptation to vainglory. In our Lord's time there were not more than five (or six) public fasts (see below), but the strict Jews, especially the Pharisees, were accustomed to fast also on Thursday (the day when Moses ascended Mount Sinai), and on Monday (the day when he came down): see Luke 18:12. Vainglorious persons fasted more frequently even than this, and were careful to advertise the fact. A faster did not wash, or bathe, or anoint the body, or shave the head, or wear sandals, but placed ashes on his head, thereby 'disfiguring his face.' It was said of a certain Rabbi Joshua, that 'all the days of his life his face was black by reason of his fastings.' Christians are directed by our Lord when fasting privately, to conceal the fact, lest they should be guilty of ostentation. This command does not apply to public fasts ordered by lawful authority. On such occasions Christians should fast publicly, both as an outward expression of obedience, and for the encouragement of others who are afraid of ridicule. All excessive fasting which would injure the body or interfere with the due discharge of social duties is contrary to Christianity. People who are strictly abstemious or temperate can fast very little with regard to the quantity of food, but it is open to them to fast with regard to its quality. To fast is also to abstain from usual and lawful indulgences and amusements, so far as can be done in charity and without attracting undue attention. The time saved can be given to prayer, meditation, visiting the sick, etc. Money saved by fasting should of course be spent in charity. The object of Christian fasting is, (1) to subdue the flesh to the spirit, and (2) to fit the mind for devotion. A fast which is not joined with prayer and devotion is no Christian fast. See further Luke 9:14; Acts 13:2; Acts 14:23; 2 Corinthians 6:5; 2 Corinthians 11:27.

What fasts were observed in our Lord's time is not quite certain. Only one fast (the Day of Atonement) was prescribed in the Law. During the exile arose the custom of observing four yearly fasts to commemorate the calamities of Jerusalem. That of the fourth month commemorated the capture of Jerusalem (Jeremiah 52:6.), that of the fifth the destruction of the city and Temple (Jeremiah 52:12), that of the seventh the murder of Gedaliah (Jeremiah 41:1), that of the tenth the beginning of the siege (Jeremiah 52:4). Of much later origin was the fast on the 13th of Adar, supposed to commemorate the advice of Haman to massacre the Jews. To what extent, if at all, these fasts were observed in Palestine in our Lord's time, is a disputed question.