1Ki 18:36 - Best witness: Let them know you are God and I am your servant!
Per Luke 18:11 Lots of churches today love to praise and proclaim the blessings of God out of a sinful motive. Which is actually praising themselves.
My note: Had it been just Luke 18:11, then one would assume the hypocrite's prayer was alright, that he gave the credit to God, though still with reservation for the language looks down on his neighbors, but v.12 clarifies the hidden motive.
Why Christians fast? Not to rely on physical forces.