Doctrine and Life: Health and Healing
"Doctrine must be pure and clean, namely, the dear, blessed, holy, and one word of God, without any addition. But life, which should daily direct, purify, and sanctify itself according to doctrine, is not yet entirely pure or holy, so long as this maggoty body of flesh and blood is alive. But as long as it is in the process of purification and sanctification, being continually healed by the Samaritan and no longer decaying in its own impurity, it is graciously excused, pardoned, and forgiven for the sake of the word, through which it is healed and purified; thus it must be called pure. This is why the holy Christian church is not a whore or unholy, because it continues to hold to and remain with the word (which is its holiness) without blemish and with strength. “You are already made clean (says Christ in John 15 [:3]) by the word which I have spoken to you,” not on your own account.
Martin Luther, vol. 41, Luther’s Works, Vol. 41 : Church and Ministry III, ed. Jaroslav Jan Pelikan, Hilton C. Oswald and Helmut T. Lehmann, Luther’s Works, 41:218 (Philadelphia: Fortress Press, 1999, c1966).