Galatians 5:4

Christ is become of no effect unto you - It is vain for you to attempt to unite the two systems. You must have the law and no Christ, or Christ and no law, for your justification.

Ye are fallen from grace - From the Gospel. They had been brought into the grace of the Gospel; and now, by readopting the Mosaic ordinances, they had apostatized from the Gospel as a system of religion, and had lost the grace communicated to their souls, by which they were preserved in a state of salvation. The peace and love of God, received by Jesus Christ, could not remain in the hearts of those who had rejected Christ. They had, therefore, in every sense of the word, fallen from grace; and whether some of them ever rose again is more than we can tell.