Some people will say they can't believe in something they can't actually see with their own eyes. I disagree, because we do it every day. We believe in the wind, but we can't see it; we only see its effects. You can't see an atom with the human eye, but you had better believe they exist because everything physical is made up of millions of invisible (to the human eye) atoms. Faith in God is much the same way. We can't see faith, but it's real and necessary to be a Christ-follower; and we can see its effect in a believer's life. In fact, the Bible tells us that it's impossible to please God without faith (Hebrews 11:6).