Hebrews 11:1 – 3 and verse 6 (ESV)
Now faith is the assurance of things hoped for, the conviction of things not seen. 2 For by it the people of old received their commendation. 3 By faith we understand that the universe was created by the word of God, so that what is seen was not made out of things that are visible.
:6 And without faith it is impossible to please him, for whoever would draw near to God must believe that he exists and that he rewards those who seek him.