it seems to be a reflection of your soul-state. The resultant effect seems to be based not only on your current state, but also the max possible for anyone(total scale). there are 6 differant effects I've noted... may be more. Not all are good, and require grey an below states of soul to see. I really like the blue and red one...

I personally feel there is a greater benefit to greater soul-state levels. I can't recall if this was confirmed or not... but it sure feels like you achieve better hits and chance to hit with the stronger levels.


Circle and Charisma seem to factor most for achieving higher max possible soul-state and the increased levels of power of your holy weapon... although while raising mine I had trained some wisdom and intelligence and discipline as well... but due in large part to the RESPEC gift we were given... I found Charisma most effectual for this.

Holy weapon can in fact, become more powerful then the strongest clerical bless even... which is nice. I had always hoped our holy weapons could achieve what a low tier spell could not.

Holy weapons have the most benefit against undead and cursed but work against any opponent type.