| Mirror's Shadow |
GMs are rare and beautiful creatures, and are to be encouraged.
Totally agree.
Anyone can learn the rules, but you can't learn enthusiasm.
Assist him by pointing out particular portions of the core rulebook that he should read. Ask him to be your GM assistant for a few sessions. He can be responsible for learning all of the rules and being the go-to guy regarding "XYZ", where "XYZ" are the rules that you feel are the most important, or where his knowledge appears to be the weakest.
In short, encourage and support him, don't shoot him down. We're a small enough hobby that every extra player and GM makes a difference. And who knows, in twenty years time, you may both look back at his start and laugh about his lack of rules knowledge when he first started, but also appreciate the twenty good years of gaming that you've had together.