I found a good write up on BoS.
Blessing of Sanctuary, the 21-point Talent of the Protection tree, grants the benefit of reducing damage done for each hit by 81.
The damage reduced by Blessing of Sanctuary is factored in before mitigation is applied.
This includes armor, block value for blocked attacks, siphoned damage due to Blessing of Sacrifice, everything.
For example;
Monster hits you for 1000
Blessing of Sanctuary reduces this by 80 (leaving 9920)
Armour reduces this by 65% (9920 x 35%, leaving 3472)
The attack was blocked, and your block value is 200 (3472 – 200, leaving 3272)
Monster hits you for 3272 (200 blocked)
compare the above to the exact same situation minus Blessing of Sanctuary;
Monster hits you for 1000
Armour reduces this by 65% (1000 x 35%, leaving 3500)
The attack was blocked, and your block value is 200 (3500 – 200, leaving 3300)
Monster hits you for 3300 (200 blocked)
In this case, Blessing of Sanctuary granted an effective damage reduction of 28 damage.
This would be equivalent to an additional 2.8% damage reduction from armour.
Blessing of Sanctuary scales in greatest effectiveness with very frequent, but less individually damaging hits being taken.
The threat dealt by Blessing of Sanctuary amounts to 87.4 threat per blocked attack with improved Righteous Fury active. (Righteous Fury should always be active)
i don’t know how you did your math, but blessing of sanctuary is not equivalent to 2.8% damage mitigation.
28/10,000 = .0028 = .28%
the key point is that blessing of sanctuary does less the more armor you have:
45% mitigation from armor = 44 less damage
55% mitigation from armor = 36 less damage
65% mitigation from armor = 28 less damage
Alright…here’s my question. While tanking, what should a paladin be using…Blessing of Kings, or Blessing of Sanctuary? I realise Sanctuary adds some additional holy damage, and reduces damage taken – but Kings Ups all stats, which will increase stamina/mana…
I’m just not sure which is the better pay off.
It’s a personal choice and often situational.
However if I had to choose from BoS or BoK, I would use BoS when I am trying to tank multiple mobs in an instance and use BoK on bosses.