Galatians 5:3-4

3Once more I solemnly affirm to every man who receives circumcision [as a supposed requirement of salvation], that he is under obligation and required to keep the whole Law.

4You have been severed from Christ, if you seek to be justified [that is, declared free of the guilt of sin and its penalty, and placed in right standing with God] through the Law; you have fallen from grace [for you have lost your grasp on God’s unmerited favor and blessing].