What is a Christian? How do they act? How do they develop? These are questions asked in every generation. These are the sort of topics covered in the book of Martin Luther quotes by Ewald Plass WHAT LUTHER SAYS under to topic THE CHRISTIAN (209-246). Below are the first two quotes under this topic, the 610th and 611th quotes in the book.
A CHRISTIAN is not a perfect but a pardoned person, says Luther in his somewhat discursive exposition of the story of Lot (Gen. 19:9-11)
610 The Term Defined Christians are people who believe in the forgiveness of sins. If, then, you believe in Christ, if you love His Word and embrace it by faith, you are a true Christian. (W 43, 64 – E op ex 4, 277 – SL 1, 1239)
CHRISTIANS, says Luther in another definition, are not spiritually self-made men, (From a sermon of Nov. 19, 1531; Roerer’s notes.)
611 Christians Are Made by Taking, Not by Giving One is a Christian, not because he gives to Christ but because he accepts from Christ. A Christian is not an active but a passive person, one who only allows things to be given to him. If you do not permit things to be given to you, you are no Christian. You are not called a Christian from what you do – for then you should be called a “worker” – but because you have Christ. How so? YHou did not make Him, as a vessel, but you had to let Him be given to you through the Gospel. This is easily said. But try it. (W 34 II, 414)
Plass, Ewald M WHAT LUTHER SAYS: A Practical In-Home Anthology for the Active Christian 209