Matthew 9:14

‘Then come to him the disciples of John, saying, “Why do we and the Pharisees fast often, but your disciples do not fast?” '

The disciples of John now approach Jesus, but it would appear possible that they had been in consultation with the Pharisees, who were clearly also commenting on the lack of fasting among Jesus' disciples. It appeared to them that their lack of fasting demonstrated a lack of sincerity, and they may well have been genuinely puzzled. The disciples of John had of course good reason to fast as an act of mourning, for their great leader languished in prison. That would make it even more reason why they should feel that Jesus' disciples should be fasting as well at what was a dark time for the godly in Israel. We have good reason to believe that the Pharisees fasted every Monday and Thursday until around 15:00 hours. It would appear possible that John's disciples may have done something similar. Then there were also voluntary fasts connected with some of the great Feasts which some of them had just been involved in.