commitment and sun...

Dear Teachers,

From Mirror, Mirror:

"He hadn't ducked from commitment to a cause, but he had learned by virtue of his foreigner status that it was sensible to keep one's mouth shut..."

What is "commitment to a cause"?

"The illuminated pages fell open and the sudden sun made of the vellum a blinding platter."

Is it saying there is a picture of sun on the page or the actual sun shines on the page?

1 He hadn't avoided the issue of supporting or believing in a causer, but knew to keep his mouth shut as a foreigner.

2 It sounds as if the real sun was reflected off the picture.

Thanks!

You're welcome, KuaiLe. ;-)