Therefore no man is able to teach pure and aright touching faith, nor to reject the righteousness of works, without sound practice and experience.
 Martin Luther, Table Talk (1566). copy citation

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Author Martin Luther
Source Table Talk
Topic experience faith
Date 1566
Language English
Reference
Note Translated by William Hazlitt
Weblink http://www.ntslibrary.com/PDF%20Books/Luther%20Table%20Talk.pdf

Context

“`tis a hard matter for a man to say: I am the child of God, and am comforted and solaced through the immeasurable grace and mercy of my heavenly Father. To do this from the heart, is not in every man’s power. Therefore no man is able to teach pure and aright touching faith, nor to reject the righteousness of works, without sound practice and experience. St Paul was well exercised in this art; he speaks more vilely of the law than any arch heretic can speak of the sacrament of the altar, of baptism, or than the Jews have spoken thereof; for he names the law, the ministration of death, the ministration of sin, and the ministration of condemnation;” source