Lutherans sure do make a big deal about faith. After all, wasn't one of the rallying cries of the Reformation known as sola fide, "faith alone"? The problem, is, do we really know how to answer the question of what the word "faith" means?
I'm sure that some Lutheran seminary professors would probably fail me if I gave this answer to the question of "what is faith", but I kind of like it anyway:
"A brother questioned Abba Poemen saying, 'Give me a word.' And he said
to him, 'The fathers put compunction as the beginning of every action.'
The brother said again, 'Give me another word.' The old man replied, 'As
far as you can, do some manual work so as to be able to give alms, for
it is written that alms and faith purify from sin.' The brother said, 'What
is faith?' The old man said, 'Faith is to live humbly and to give alms.'"
(From p. 115 of "Oasis of Wisdom: The Worlds of the Desert Fathers and Mothers" by David Keller).
A friend of mine who follows this blog likes to remind us Lutherans about the question posed at Luke 10:29 - "Who is my neighbor?" That question, of course, was asked by the lawyer who wanted to justify himself before Jesus (as a I lawyer, I admit that I sometimes resemble that remark). In response to the lawyer's question, Jesus did not give the lawyer a systematic theological analysis - he told him the parable of the Good Samaritan.
So, that is why I like Abba Poemen's answer to the question of "what is faith?" Like Jesus, he didn't give a detailed theological explanation; just a few words which suggest that faith is intertwined with doing what Christ calls us to do - to live humbly and to give alms.