The "Other Gospel" Paul Speaks of in His Epistle to the Galatians

In his letter to the Galatians, Paul attacks "another gospel." I marvel that ye are so soon removed from him that called you into the grace of Christ unto another gospel: Which is not another; but there be some that trouble you, and would pervert the gospel of Christ. But though we, or an angel from heaven, preach any other gospel unto you than that which we have preached unto you, let him be accursed. As we said before, so say I now again, If any man preach any other gospel unto you than that ye have received, let him be accursed.^{Galatians 1:6-9}

However, Paul does not immediately say which gospel he is talking about. We have to continue reading on to find that Paul identifies the other gospel as the gospel of the circumcision. But contrariwise, when they saw that the gospel of the uncircumcision was committed unto me, as the gospel of the circumcision was unto Peter.^{Galatians 2:7}

Since this is the only other gospel that Paul speaks about in his letter, we can conclude that Peter's gospel is that "other" gospel that Paul writes about in Galatians 1:6-9. Accusing your fellow apostles' gospel as being false would stir discourse among the people, and thus would not be an action that a true apostle, as Paul claims to be, would do.

Value of this Evidence

This evidence against Paul is rather weak. Paul could be attacking a third gospel from another yet. Yet that this interpretation exists as a valid one is concerning.