“For if you forgive others for their transgressions, your heavenly Father will also forgive you. But if you do not forgive others, then your Father will not forgive your transgressions” (Matthew 6:14-15).
Federal Visionists love verses like this because they think that Jesus is making the forgiveness of our sins contingent upon whether we forgive the sins of others. Obviously, this is as Pelagian as the day is long.
The Reformed faith has always insisted that we receive the forgiveness of sins in justification by faith alone. Whether we forgive the sins of others has nothing to do with the forgiveness of our sins.
In this passage, Jesus was simply restating the demands of the law to show us the futility of trying to obey. If you forgive others, then you are putting yourself back under the law. Faith means that we rest in Christ by refusing to forgive others.
Frankly, we are a little puzzled at this statement by Jesus. Unfortunately, we cannot just call him up on the telephone to find out what he meant. However, if we could, we are sure that Jesus would re-align himself with Reformed tradition. He was such a fan of traditionalism, in general.