"No it isn't. It is a commitment to be led by evidence." That means you're faithful of the evidence. Faith and belief are almost the same thing if not the same thing. Even the evidence that can be verified by anyone can be mistaken. But honestly, that's not the case most of the time but it's always possible. And people have believed incredible things forever without evidence but eventually it turned out to be true. You never know, you could say that now, but there could be refutable evidence that a God does exist some day. But I see that you are not too competent on possibility which is understandable, cofty.
"If they want to claim their belief is rational then let's hear the evidence." Christians believe in God based on the testimony and evidence supplied to them by those who were in a position to receive the evidence when it was available, even though we are not able to verify that evidence empirically today because it is no longer available to us. Whether it's true or not is up to the person to decide. It's just like future scientists should believe in the cosmology described by today’s scientists based on the evidence they acquired when such evidence was available, even though future scientists will not be able to verify that same evidence empirically in their own day.