For those who were attempting to be doers of the law, God required the Jewish people under that law to obey all of it (which no one ever did). On the flip side ... Paul told believers in Christ that if they were going to attempt to cling to even one commandment from the law (such as circumcision), they would be obligated to keep the whole law package (containing 613 line items). The result would be a falling away or distancing from grace. He also articulated that if a single law could give life and righteousness, then those things would have been provided by such a law. But life comes by faith in a living Christ—not a religious system of works that seeks to establish phony self-righteousness.
