Legality
There were many laws etched into the jade slip, including all kinds of legal jargon with clauses and conditions. It would take some time for them to go through all of it, but they understood the gist of it.
For example, they could kill their enemies. It was pretty simple.
However, they cannot harm innocents or people who did them no wrong unless they belong to the enemy group. There were a lot of clauses explaining the intricacies, even about taking them prisoners and deciding later and whatnot.
But the one that had them smiling and soul-whispering to each other was the Marriage Act.
The Marriage Act allowed their male descendants to stay married to three wives at the same time, but only with the explicit and written consent of the first wife and the second wife. However, there were also other requirements for the second marriage and third marriage that needed to be fulfilled before they could take on the second wife and third wife.