Mark 11:25 But when you are praying, first forgive anyone you are holding a grudge against, so that your father in heaven will forgive you your sins too.
This is Jesus’ answer to the disciples’ desire to work miracles. It is straightforward for him – grudges and dissatisfaction are obstacles to the expression of God’s power. However deeply buried, unforgiveness will always work out in lack of faith, because unforgiveness is rooted in a selfish world-view. Releasing others and ourselves from grudges is absolutely necessary for a continuing Christian walk, as well as the only way to see God’s power work through our lives.
In fact, it is so much the prioriry that Jesus has changed the conversation here from one about miracles in the world to being about the greatest miracle we can experience: forgiveness of our own sins and justification with God. It’s not in keeping with Jesus’ lessons of a good father or the Hebrew scriptures to launch from this verse into a validation theology – that our salvation is dependent upon our forgiveness of others – but it is fairly observable that unforgiveness presents an experiential obstacle to appreciating our salvation!
Taking Jesus at his simplest here and in the previous verses, all I can see is that he links our ability -or desire – to really believe in God with the degree of intimacy we have with him, and unforgiveness and grudges, regrets and other unhealthy emotions obstruct that intimacy, not because He is unable to surpass them but because we become preoccupied with them! How wonderful that one promised day, we will no longer have to fight to keep our attention on God – and that every believer is in the process of being changed into this place by God’s sanctifying Spirit.
It is our job while here on earth, through God’s Holy Spirit, to present ourselves as living sacrifices, blameless and acceptable – to work out our salvation by engaging with the process by which the Spirit of God changes us to resemble Jesus. So be free of anger and hold no grudges and see God’s power work through you.