Fasting was voluntary in the early Christian Church. It was charged by his enemies that Christ's disciples "fasted not," while those of John did fast (Matt. 11:18,19). Our Lord did not positively enjoin religious fasting, and indeed he alluded in terms of censure to the frequent fasts of the Pharisees. His reference to the time which would come when, being deprived of the personal presence of the bridegroom, his disciples would fast, implied rather a season of general mourning than of self-denial. In the Sermon on the Mount (Matt 6:17) he recognizes the practice, but leaves the frequency and extent to the individual judgment. Fasts were undoubtedly observed by the early Christians (see Acts 13:2, 14:23; II Cor. 6:5), but these were probably a recognition of old established usage, handed down through generations. When it is remembered that a very large portion of the Christian Church was originally Jewish, it is not surprising that fasting, which was so marked a feature under the old dispensation, should have been handed down from age to age and that it should be occasionally found to some extent in the church even at the present day. That it has merits, both spiritual and physical, may not be gain said. A sincere fast, which while mortifying the flesh, aided in concentrating the mind upon the things of the Spirit, is especially adapted to certain great emergencies. Our Saviour himself set us the example.
