Sel 'adam: When you are attacked, if a card ability gives a bonus to the attack roll, your defense roll gains +2.
Bitha: When you are attacked, before rolls are made, you may choose to discard this card. If you do, the attack deals -2 damage, to a minimum of 0.
When David went to fight Goliath, King Saul offered David his armor. It was too large then, so David did not take it.