“And when they were come to the multitude, there came to him a certain man, kneeling down to him, and saying, Lord, have mercy on my son: for he is lunatic, and sore vexed: for ofttimes he falleth into the fire, and oft into the water. And I brought him to thy disciples, and they could not cure him. Then Jesus answered and said, O faithless and perverse generation, how long shall I be with you? how long shall I suffer you? bring him hither to me. And Jesus rebuked the devil; and he departed out of him: and the child was cured from that very hour. Then came the disciples to Jesus apart, and said, Why could not we cast him out? 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. Howbeit this kind goeth not out but by prayer and fasting.” – Matthew 17:14-21
In this account we see a boy who is possessed of devils and in need of deliverance. Yet for all their trying the disciples could not cast them out, so Jesus did. Later they asked Him privately why they could not cast these demons out and He gave them two different answers. At the first He tells them that they could not because of unbelief. If they truly believed then it would have been possible.
Now this “belief” needs to be dissected a bit because it is more often then not misunderstood. When most people read this they think, well whatever I choose to believe, if I believe hard enough it will happen. This just isn’t so. No matter how much you believe in a lie, it’s still a lie. No matter how much you believe in an idol, it’s still an idol. And no matter how much you believe in your own belief it’s still only your belief and there is no power in that because no greater power backs that up. However, if you believe in what God tells you then He will back up His impossible words with His impossible power and you will see His impossible results. You can’t just say, “I want this to happen so I will believe that it will and it will“, there’s no power in that. But if God tells you something will happen, then you can say “I know this will happen if I believe what God has told me and trust Him enough to step out in obedience (which is faith expressed)“, then you can be assured that it will happen because “God’s” power is in that and not your own.
“And this is the confidence that we have in him, that, if we ask any thing according to his will, he heareth us:” – 1 John 5:14
“So then faith cometh by hearing, and hearing by the word of God.” – Romans 10:17
You see, faith without the action of prayer and fasting will not cast it out. Neither will the action of prayer and fasting without faith. It takes faith and action because the faith must drive the action and the action must prove the faith, therefor is trust perfected and proven by the obedience of the action. It is important to not simply have a belief in your belief (or your faith is actually in yourself), but rather to intently seek God for His will, get His instructions, and believe what “He” says so you can move with the authority of His power backing His words and will, rather than your own authority backing your own words and will.
Now having said that, the disciples did have this word from the Lord or else He would not have told them that they failed to believe. Jesus called them faithless, meaning they did not completely trust what He told them. Trusting in what God says to the point that your actions reflect it, is the essence of what faith really is and this is what they lacked.
Howbeit, though Christ makes it clear that though this was what hindered them, even if they had the faith to cast them out, these demons can only be expelled by prayer and fasting. Remember that Jesus’s disciples did not fast while He was with them, however Jesus did, as did His disciples after His departure. This verse is so critical and damaging to the powers of hell that it has been altered or completely removed from most modern bible translations in an attempt to hide its delivering, chain breaking, overcoming power from the saints of God. Many demonic possessions, influences, and hindrances, many bondages, burdens, and strongholds, many struggles in people’s lives and situations can only be overcome by prayer and fasting. Why? For the same reason the disciples failed… Because it takes faith, which equates to trusting what God says to the point of obeying it. So if Jesus says it takes prayer and fasting then believe Him and just do it! God’s grace affords us power to overcome Satan, but only on God’s terms, not on ours. That’s why scripture tells us that He gives more grace (which is the favor and power of God) to the humble. Because the humble don’t only hear God, they obey God, because they trust more in His words, will, and power, then their own.
“But be ye doers of the word, and not hearers only, deceiving your own selves.” – James 1:22
“But he giveth more grace. Wherefore he saith, God resisteth the proud, but giveth grace unto the humble. Submit yourselves therefore to God. Resist the devil, and he will flee from you.” – James 4:6-7