Today’s text concerns the battle between faith and unbelief. But this battle is not one that Christians wage against non-Christians. Rather, it’s a battle that Christians are engaged in against their own sinful nature. To His disciples Jesus says, “Have faith in God. Truly, I say to you, whoever says to this mountain, ‘Be taken up and thrown into the sea,’ and does not doubt in his heart, but believes that what he says will come to pass, it will be done for him. Therefore I tell you, whatever you ask in prayer, believe that you have received it, and it will be yours.” And the Apostle John writes, “This is the confidence that we have towards Him, that if we ask anything according to His will He hears us. And if we know that He hears us in whatever we ask, we know that we have the requests that we have asked of Him.” But James writes, “...the one who doubts is like a wave of the sea that is driven and tossed by the wind. For that person must not suppose that he will receive anything from the Lord; he is a double-minded man, unstable in all his ways.”
And so, often times it seems that our prayers aren’t being answered, either because we are not asking according to the Lord’s will, or because we ask with doubt. But that’s what the battle between faith and unbelief is all about. At one time, we might have the faith to move a mountain, but we’ll ask according to our will and not the Lord’s. At another time, we might ask according to the Lord’s will, but we’ll doubt that He hears us, that He’s willing to answer us, or that He’s even able to grant us our request. It’s a common predicament for every Christian that one minute he’s able to trust in the Lord with all his heart and not lean on his own understanding, while the next minute, like the man in today’s Gospel text, he’s wondering whether the Lord can do anything to help him or not. Then we hear words like, “Apart from faith it’s impossible to please God,” and we conclude, “Since I doubt, I’m not pleasing to God; therefore, God doesn’t hear me and won’t answer me, just like I was afraid He wouldn’t in the first place,” and the whole thing snowballs, so that we throw up our hands in despair, because we know we can never believe as strongly as we should and not doubt. “All things may be possible for the one who believes,” but since my faith is weak, nothing appears to be possible for me.
And nothing would please the devil more than to hear you say that. Nothing would make him happier than for you to despair of your Savior’s help and salvation, because your faith isn’t strong enough. Is doubt a sin? Is it a sin to have weak faith? Of course it is! But just like all other sins, this sin too was atoned for with the blood of Jesus shed on the cross. And so it also falls under all those sins that we confess we are guilty of before God. As John writes, “If we confess our sins, He is faithful and just to forgive us our sins and to cleanse us from all unrighteousness.” When God convicts you of your doubt and disbelief, He doesn’t do it to show you that your situation is hopeless, as the devil would have you believe. Instead, He does it, so that you will confess your sin and look to your Savior for forgiveness and help. It’s just what this father does in today’s Gospel text. He had brought his son to the Lord’s disciples, hoping that they might be able to cast out the demon that possessed him, but because of their unbelief they weren’t able to. This affected the man’s faith in what Jesus Himself could do: If His disciples couldn’t do it, could He? And so with his words, “If you can do anything,” the father betrays his doubt as to whether or not Jesus could help him.
Hearing these words, Jesus convicts the man of his unbelief with a bit of a rebuke: “If you can?” He says. “All things are possible for one who believes.” But in saying this Jesus doesn’t want the father to walk away in despair. Instead, He intends to lead the man to confess his sin of unbelief. With his words, “I believe! Help my unbelief!” the father acknowledges his weak faith to the Lord and asks for the strength to believe as he ought to. Notice that even with the weak faith that the man has, he asks the Lord for stronger faith. And that’s where we are to go, too, when we find that our faith is weak - to the Lord. Jesus doesn’t want you inspecting your faith to see how strong or weak it is. Your faith is strong or weak based on how strong or weak you think your Savior is. The stronger your Savior is, the stronger your faith will be; the weaker your Savior is, the weaker your faith will be. Jesus helps the man’s faith by doing what he requests - casting the demon out of his son. In this way He shows the man what kind of Savior he has. He is a Savior who is stronger than the demons. When He commands, they must obey.
Jesus’ disciples, too, must learn this lesson, because they struggled with unbelief as well. When they ask the Lord why they couldn’t cast out the demon, Jesus says, “This kind cannot be driven out by anything but prayer,” which is another way of saying that they needed to trust in God’s strength and not their own in trying to exorcise this unclean spirit. Perhaps they had grown a little overconfident and arrogant, having been sent out earlier with the Lord’s command to proclaim repentance to people and to cast out demons and heal the sick. Maybe they had come to believe that the power to do these things lay within themselves rather than in God. Their belief had then been misplaced and was no longer in their Lord. And so with His words Jesus reminds them of the importance of prayer and asking for God’s help and His will to be done in these situations.
And our battle against unbelief is the same as theirs. Sometimes, like this father, we doubt whether the Lord has the ability to do what we request of Him, and so we think some things are too big for Him to handle. Sometimes we ask Him for things He hasn’t promised us, and when He doesn’t grant them to us, we get upset with Him and wonder whether He really cares for us or not. Sometimes, like the disciples, we get a little cocky and place our faith in ourselves and our own abilities rather than in the Lord and His, and we stop praying to the Lord altogether. And sometimes we get caught up concentrating on our faith and how to make it grow bigger and stronger, rather than focusing on our Savior and realizing how big and strong He is.
The answer to this problem is for us to confess with this father, “Lord, I believe! Help my unbelief!” By this we are not taking credit for any faith that we might have (no matter how much or how good it might be). “Faith comes by hearing the word about Christ.” Through the hearing of the Word of the Gospel faith is created and through the hearing of that same Word faith is sustained and strengthened. Consider how impossible it was for you to believe this Gospel in the first place! As the Scripture says, “The natural man does not accept the things of the Spirit,” and “The preaching of Christ crucified is a stumbling block to Jews and foolishness to Gentiles,” and also “You were dead in your trespasses and sins.” But God did the impossible. “Being rich in mercy and because of the great love with which He loved us... He made us alive together with Christ,” and “By grace you have been saved through faith, and this is not your own doing; it is the gift of God, not a result of works, so that no one may boast.” And so, when we pray the prayer, “Lord, help my unbelief,” what we are asking of the Lord is that He who brought us to faith in Christ in the first place would continue to strengthen our faith in Him, so that we might not fall into unbelief or put our faith in someone or something else, but trust Him completely to help us in our time of need.
As He did in the beginning, the Holy Spirit continues to do now, drawing us to our strong Savior’s cross where Jesus did what was impossible for us to do, giving His life as the sacrifice for our sins, casting out the devil, appeasing God’s wrath, overcoming death and the grave by His resurrection. Concerning this the Apostle Paul writes, “He who did not spare His own Son but gave Him up for us all, how will He not also with Him graciously give us all things?” And so Jesus instructs His disciples, “Truly, truly, I say to you, whatever you ask of the Father in my Name, He will give it to you. Until now you have asked nothing in my Name. Ask, and you will receive, that your joy may be full.” Since God has given us the greatest gift of all - salvation in Jesus, He will withhold no other good gift from His children, baptized in His Name, who pray to Him, trusting in Him to grant them the things that their Lord has taught them to ask for. God has a perfect track record of keeping His Word. He has not failed to keep one of His promises. As Paul writes, “All the promises of God find their ‘Yes’ in [Christ].”
And so Jesus says to us who are weak in faith, “Ask, and it will be given to you; seek and you will find; knock, and it will be opened to you. For everyone who asks receives, and the one who seeks finds, and to the one who knocks it will be opened. Or which one of you, if his son asks him for bread, will give him a stone? Or if he asks for a fish, will give him a serpent? If you then, who are evil, know how to give good gifts to your children, how much more will your Father who is in heaven give good things to those who ask Him!”
The battle between faith and unbelief is won by the Word of God. The more you know the Word of God, the stronger your faith in Christ will be, the less you will doubt when you offer up your requests to Him. And when your faith is weak, confess that to Him and ask Him to help you in your unbelief. He’ll direct you back to His Word, where He’ll again show you your strong Savior. For those who believe in Him, all things are possible, and not only possible, but given as our inheritance in Jesus. Amen.