There is much covered by Luther’s axiom that we should let God be God.  It is a good definition of sin when we don’t.  Mercy work where the right hand doesn’t know what the left hand is doing is also a way of looking at life and letting God be God.  The gift of faith is also a matter of letting God be God –

 

“They (the sophists) say the Scriptures are far too weak that we should silence
heretics with them; reason must do it, and it must come forth from the brain; thus
one must prove that the faith is the right one. But our faith is above all reason,
and it alone is the power of God. Therefore, if the people will not believe, then be
silent; for you are not held to compel them to receive Scripture as God’s book or
Word; it is enough if you give the reason therefor. But if they take exceptions and
say: You preach that one should not hold to man’s doctrine, and yet St. Peter and
Paul, and even Christ, were men — when you hear people of this stamp, who are so
blinded and hardened as to deny that what Christ and the Apostles spoke and wrote is
God’s Word, or doubt it, then be silent, speak no more with them, and let them go.
Only say: I will give you reason enough from Scripture; if you will believe it, it
is well; if not, go your way. Will you say: Then God’s Word must suffer defeat?
Leave that to God!”

Martin Luther