Sanctity of the Dwarven Race
The dwarves were the last of the descendant races to be created, yet they were the ones chosen by Yemekar as they fulfilled all he wished his perfect creation to be. Yemekar created the dwarves with one purpose; the protection of Yemekar's Balance. Because of this holy task requires an inherent holyness the dwarves themselves like their beards are considered holy. Not only because they where created by Yemekar, but because they were chosen to fufill a holy task by the smith of the universe. Because of this holyness a dwarven life is sacred. Hence, a dwarf should never spill the blood of a fellow dwarf, not only because they are kin, but because by doing so they are attacking a being chosen by Yemekar to protect his balance. If a dwarf murders another dwarf he losses the inherent holiness granted to him/her by Yemekar and hence can be killed like any other as he has no more purpose in life. Only by achieving forgiveness can a kinslayer be given his/her holiness back. If a dwarf kills a dwarf in self defense said dwarf cannot be considered a kinslayer as he was just trying to protect the holy life of a dwarf (himself), and the attacker lost his holyness once he/she dared to go against Yemekar's wishes and tried to kill another dwarf.