A person simply is not justified by the works of the Law.
 Martin Luther, Commentary on the Epistle to the Galatians (1535). copy citation

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Author Martin Luther
Source Commentary on the Epistle to the Galatians
Topic work
Date 1535
Language English
Reference
Note Translated by Theodore Graebner
Weblink http://www.gutenberg.org/files/1549/1549-h/1549-h.htm

Context

“For the sake of argument let us suppose that you could fulfill the Law in the spirit of the first commandment of God: "Thou shalt love the Lord, thy God, with all thy heart." It would do you no good. A person simply is not justified by the works of the Law. The works of the Law, according to Paul, include the whole Law, judicial, ceremonial, moral. Now, if the performance of the moral law cannot justify, how can circumcision justify, when circumcision is part of the ceremonial law?” source