Hebrews: Faith, that is the sole theme of this chapter with many examples to buttress that theme. I think much of the faithful we see at work here stems from a willingness to obey God irrespective of how illogical it may sound to us. Noah building an ark in a comparative wilderness while middle-aged (only 600 years old). He was obedient and did build very likely at the mocking of his neighbors. He kept on going. Abraham was a scant 75 when he pulled up stakes (literally) and set off on his own to places unknown. There are others.
New Testament: Hebrews 11:1-12
Old Testament: Genesis 12:1-7