"Then Jesus said to the disciples, 'Have faith in God. I tell you the truth, you can say to this mountain, "May you be lifted up and thrown into the sea," and it will happen. But you must really believe it will happen and have no doubt in your heart. I tell you, you can pray for anything, and if you believe that you’ve received it, it will be yours. But when you are praying, first forgive anyone you are holding a grudge against, so that your Father in heaven will forgive your sins, too'" (Mk. 11:22-26).

I was particularly challenged by the words "and have no doubt in your heart", but this amazing and spectacular promise has three conditions: we must speak to the mountain; not entertain doubts and forgive all others.

Let's look at the last first because Jesus tells us to do just that. "First forgive anyone you are holding a grudge against, so that your Father in heaven will forgive your sins, too." We are to keep no record of wrongs – actual or perceived – but to unconditionally forgive everyone of everything without exception. It is good to review this daily. "Forgive us our sins as we have forgiven those who sin against us" is part of the Lord's Prayer, which is followed by "If you refuse to forgive others, you Father will not forgive your sins" (Mt. 6:9-15). Leon Morris comments: "To refuse to forgive others is to demonstrate that one has not felt the saving touch of God".

When Jesus made this promise he may well have been looking directly at the literal Mount of Olives and thinking of Zec. 14 where it gets split in two at his second coming and the area becomes one vast plain. But in context his use of the word "mountain" can have many applications. A mountain becomes any obstacle in the way of God's perfect will being accomplished.

How are we to interpret "no doubt in your heart"? William Lane writes: "These solemnly introduced assurances are grounded explicitly on God's faithfulness and not on the ability of a man to banish from his heart the presumption of doubt". It reminds me of Jm. 1:6 "when he asks, he must believe and not doubt, because he who doubts is like a wave of the sea … he is a double-minded man". James is describing a man who is trying to face in two directions at the same time: having faith in God and not having faith in God. Lane seems to be describing a man unsure about God's faithfulness. Neither are referring to "perfect" faith. Even weak faith can produce miracles!