I have done both and I think either would work on a Bible cover. The paint may be a little more user friendly. Put it on thinned, and build up layers to get your coverage. If you go with the gold leaf, make sure the leather is dry first. I also did all my other color before applying it. Make sure all the other color is dry. When you brush to burnish it, you are going to get gold leaf over everything, and it takes some patience to get it all removed. You will also get gold leaf stuck to wherever you apply the glue, so becareful with it. I would do several light sealing layers over it- letting each layer dry before adding another. Good luck! And it's never a bad thing to do some test tries first!