William Barclay's Daily Study Bible - Mark 2:18-20
2:18-20 The disciples of John were in the habit of fasting, as were the Pharisees. So they came to Jesus and said, "Why do John's disciples and the disciples of the Pharisees fast, while your disciples do not?" "Surely," Jesus said to them, "his closest friends cannot fast while the bridegroom is still with them? So long as they have the bridegroom they do not fast. But the days will come when some day the bridegroom will be taken away from them--and then, in that day, they will fast." ... read more
Matthew Henry's Complete Commentary - Mark 2:18-28
Christ had been put to justify himself in conversing with publicans and sinners: here he is put to justify his disciples; and in what they do according to his will he will justify them, and bear them out. I. He justifies them in their not fasting, which was turned to their reproach by the Pharisees. Why do the Pharisees and the disciples of John fast? They used to fast, the Pharisees fasted twice in the week (Luke 18:12), and probably the disciples of John did so too; and, it should seem, this... read more