(Hebrews 11:1 NKJV) Now faith is the substance of things hoped for, the evidence of things not seen.Some people wrongly assume that faith is just another word for gullibility. For them, faith means believing in things for which there is no empirical evidence. For them, faith is accepting what you are told - hook line and sinker - no matter how bizarre or illogical. For them, faith is primitive superstition used to explain things primitive people don't understand.
But the Bible consistently links the idea of faith to knowledge.
(2 Corinthians 8:7 NKJV) But as you abound in everything—in faith, in speech, in knowledge, in all diligence, and in your love for us—see that you abound in this grace also.Biblical faith is believing in things that cannot be proven to the satisfaction of a skeptic - but that doesn't mean there is no genuine evidence for the things that are believed.
(2 Peter 1:5 NKJV) ¶ But also for this very reason, giving all diligence, add to your faith virtue, to virtue knowledge,
As a child I was taught that the Bible was the inspired word of God - and I believed it. That might have been my childish gullibility. But as I got older (and more skeptical,) I grew in my experiential knowledge of the Bible, the physical world, the people in the world, etc. In my case my faith grew stronger with my increased knowledge. What I find in the Bible is consistent with what I find in the world around me. The things in the world match what the Bible says about them. The people in the world are just like the Bible describes them to be. That helps me accept by faith the statements of the Bible that I cannot test by experience.
Some people are frustrated that their ideas about things like macro-evolution cannot be proven to the satisfaction of a skeptic. But it isn't like they can do an experiment in which life springs into existence from nothing or evolves an eye on demand. They say it makes sense because there is such a thing as changes in living things through adaptation. They say is is the only truly "scientific" explanation because it doesn't include recourse to the supernatural.
But the more I know about the world and the people in the world, the more it is clear that macro-evolution doesn't fit the facts. To believe it I would have to swallow the complete LACK of evidence for complex systems developing themselves and for complex codes compiling themselves. I would need to ignore all the evidence to the contrary - the physical laws by which systems tend toward disorder and everything moves toward entropy. I would also have to believe - against all I observe in myself and others - that good and bad and right and wrong have no objective meaning. That there is no purpose or meaning in human existence. That there is no ultimate justice.
So what is faith and what is gullibility? For me, faith corresponds with the evidence that is available - even the scientific evidence.