For in Jesus Christ neither circumcision avails anything, nor uncircumcision; but faith which works by love.
All Commentaries on Galatians 5:6 Go To Galatians 5
Augustine of Hippo
AD 430
This is the faith that separates the righteous from the unclean demons, for they too, as the apostle James says, “believe and tremble,” but their actions are not good. Therefore they do not have that faith by which “the righteous live.”