Judgement of Light is not currently scaling with spellpower grandted from Sheath of Light. It is scaling with spellpower form all other sources that I have tested. I have not tested Touched by the Light. This is an issue on Live, and the current PTR build. The tooltip does indicate that it's scaling with Sheath, but the actual effect is always lower than the dynamic tooltip by 10% of the spellpower granted from Sheath of Light.