I am not sure that is true either. God made me 6'2" and I weighed 235 lbs in combat trim. I have been able to unscrew a little guy's head most of my life. Is that the god's law you are referring to.......or should the little guy have the same rights to defend himself (man's law)
I believe the right to defend yourself is a natural/ god given right.
Something about selling your cloak to buy a sword.....