Prayer and fasting - See on Matthew 17:21 (note).

This demon may be considered as an emblem of deeply rooted vices, and inveterate habits, over which the conquest is not generally obtained, but through extraordinary humiliations.

This case is related by both Matthew and Luke, but it is greatly amplified in Mark's account, and many new circumstances related. Another proof that Mark did not abridge Matthew.

And he said unto them,.... Matthew, besides the following reason, assigns another, as given by our Lord, why they could not cast out the foul spirit, which was their unbelief; of which they were guilty in some sort, as well as the Jews, and the father of the child; but Mark omits it, and only relates this as the reason;

this kind can come forth by nothing, but by prayer and fasting; which they had not observed; See Gill on Matthew 17:21.

And he said unto them, This kind can come forth by nothing, but by prayer and fasting.

9:29 Can come forth by nothing, but by prayer. Fasting is omitted in the Revised Version, but placed in the margin. The faith which will be effectual must be a faith exercised in prayer. The work of the Church is still to cast out devils, the unclean spirits of worldliness, selfishness, greed, infidelity, lust, intemperance, Sabbath-breaking. These still defy the ordinary efforts and faith of God's people. We have faith enough for ordinary duties, for some giving, for prayer-meetings, for building churches; but there is a work which ordinary faith cannot do. How shall we get that higher faith? By prayer and fasting. By such an earnestness that we forget the needs of the body.

Margin This

See, 1Ki 18:42-45 Acts 13:2 The two best MSS. omit "and fasting." Cf. Mt 17:21

29. And he said unto them, This kind can come forth by nothing but by prayer and fasting-that is, as nearly all good interpreters are agreed, "this kind of evil spirits cannot be expelled," or "so desperate a case of demoniacal possession cannot be cured, but by prayer and fasting." But since the Lord Himself says that His disciples could not fast while He was with them, perhaps this was designed, as Alford hints, for their after-guidance-unless we take it as but a definite way of expressing the general truth, that great and difficult duties require special preparation and self-denial. But the answer to their question, as given in Mt 17:20, 21 is fuller: "And Jesus said unto them, Because of your unbelief. For verily I say unto you, If ye have faith as a grain of mustard seed, ye shall say unto this mountain, Remove hence to yonder place, and it shall remove; and nothing shall be impossible unto you" (Mt 17:20). See on [1463]Mr 11:23. "Howbeit this kind goeth not out but by prayer and fasting" (Mt 17:21), that is, though nothing is impossible to faith, yet such a height of faith as is requisite for such triumphs is not to be reached either in a moment or without effort-either with God in prayer or with ourselves in self-denying exercises. Luke (Lu 9:43) adds, "And they were all amazed at the mighty power of God"-"at the majesty" or "mightiness of God," in this last miracle, in the Transfiguration, &c.; or, at the divine grandeur of Christ rising upon them daily.

Second Explicit Announcement of His Approaching Death and Resurrection (Mr 9:30-32).

9:14-29 The father of the suffering youth reflected on the want of power in the disciples; but Christ will have him reckon the disappointment to the want of faith. Very much is promised to our believing. If thou canst believe, it is possible that thy hard heart may be softened, thy spiritual diseases may be cured; and, weak as thou art, thou mayest be able to hold out to the end. Those that complain of unbelief, must look up to Christ for grace to help them against it, and his grace will be sufficient for them. Whom Christ cures, he cures effectually. But Satan is unwilling to be driven from those that have been long his slaves, and, when he cannot deceive or destroy the sinner, he will cause him all the terror that he can. The disciples must not think to do their work always with the same ease; some services call for more than ordinary pains.