“Truly, I say to you, if you have faith and do not doubt, you will not only do what has been done to the fig tree, but even if you say to this mountain, ‘Be taken up and thrown into the sea,’ it will happen. 22 And whatever you ask in prayer, you will receive, if you have faith.”
Jesus had cursed a fig tree that only had leaves, but no fruit (In Palestine the fig trees produced fruit before the leaves came forth). The text record that the fig tree withered at once. And in this Jesus taught the Apostles a lesson. A lesson about faith. Consider what John MacArthur writes abou this passage (Emphasis mine)…
Jesus was speaking about faith in the true God and in God alone, not faith in one’s dreams, aspirations, or ideas of what he thinks ought to be. Mountain-moving faith is unselfish, undoubting, and unqualified confidence in God. It is believing in God’s truth and God’s power while seeking to do God’s will. The measure of such faith is the sincere and single desire that, as Jesus said, “the Father may be glorified in the Son.”
True faith is trusting in the revelation of God. When a believer seeks something that is consistent with God’s Word and trusts in God’s power to provide it, Jesus assures him that his request will be honored, because it honors Him and His Father. When God’s commands are obeyed He will honor that obedience, and when any request is asked in faith according to His will He will provide what is sought. To do what God says is to do what God wants and to receive what God promises.
The faith that moves mountains is not to be seen as asking God to grant answers to our selfish prayers, but rather the answers He promises when we ask anything according to His will that is for His glory. THOSE are the prayers prayed in faith that God answers.