There is many definitions explains what is actually faith, to me all of them seem to be incorrect in some areas. I’ve been looking after a real importance or characterization of faith. Here is what I found, God’s words about faith:

“Now faith is the substance of things hoped for, the evidence of things not seen.”
Hebrews 11:1

Faith is so real that its actually called a substance. The Greek word used here for substance is hypostasis (ὑπόστᾰσις). It literally means “that which stands under” something else or “provides the basis for” something else (Prince, Derek. Faith to live by. 1977).

Faith vs. Hope
What is the difference between faith and hope?
The first main difference is that faith is in the heart, while hope is in the mind.

“For with the heart man believeth unto righteousness.”
Romans 10:10

Discipline our Self Control - means to do what you know you should do, when you don't feel like doing it.