This is a great point. We cannot observe evolution; we can only observe fossils. Macro evolution has never been observed by man; so to believe in it requires faith.
Requires evidence, not faith. Just because you have not directly observed something does not mean it is impossible to know anything about it. Evidence is left behind by which inferences can made. For example, a crime scene investigator gathers evidence about a crime and deduces facts about the circumstances. It's not based on faith but on logical reasoning from available evidence. Evidence, such as the decay of radioisotopes is very good evidence. It doesn't serve the religious position well to deny that anything can be known about the distant past because not everything is known, or to deny the role of deductive reasoning, or physical laws. The epistemology of faith and science are completely different. The Bible does not have to be a science or history book to be religiously true.
[ame]http://www.youtube.com/watch?v=lBOgH5f36cQ&feature=related[/ame]