Regarding the oaths discussion. Doesn’t the precedence of an oath comes close to an unlawful order concept? And shouldn’t that be true regardless of oaths? And, lastly, isn’t it all expecting too much of a modern thinking from pre-modern people?

The idea of an unlawful order is pretty new, really dating back only to WWII, although the roots could be said to go back to the Geneva and Hague Conventions of the 19th century. 

The idea of precedence is a simpler one, rooted in some of the oldest legal precepts out there.