
He is telling those who receive circumcision-in other words attempt to justify themselves through the rites and rules of the Law-that Christ will be of “no benefit” to them. He says to those who let themselves be circumcised (Galatians 5:2) that they are “trying to be justified by law” and have therefore “been alienated from Christ you have fallen away from grace.” It should be noted that there is no mention of salvation or the security of the believer. In Galatians 5:4, the context is Paul’s warning against mixing law and the Gospel to attain justification.

But because of the biblical doctrine of the perseverance of the saints, we know the warnings cannot be directed at true believers in Christ because once grace has been obtained, believers cannot fall from it. Galatians 5:4 and its reference to falling from grace is one of those “ warning passages” pointed to by those who reject the doctrine of the eternal security of the believer.
