I think this would also affect passive skills (as no exceptions are mentioned). There's also a BH card that blocks abilities and it is commonly interpreted that it blocks passive skills too so I'd interpet Silence the same way.
Just remember that Silence also affects friendly models so this really is a double-edged sword
I'd be inclined to play it as only affect abilities that require resources to play since it says RES(+2). I read the +2 as meaning +2 on what you already are spending. And since passives don't need resources spent on them, the spend RES(+2) doesn't apply. If it said RES(2) to use an ability maybe that would mean all abilities, but making someone pay to use passives is a biggie, and I think it would specifically mention that it affects passives if that was the case.
Good I have a doubt, and it may be interesting that those of Prodos are pronounced in it, because I see something strange in the rule.
The power of the cardinal dominic The silence:
The Silence: RES(3): No other model may use any ability unless they spend RES(+2) per ability (weapons are unaffected).
and my question is all the skills that must be activated as well as passive ones?
Passive skills (Ranger, Heal, Camouflage, ...) are what I mean.
Thank