The correct answer to this open question is the following.
My letter would be the following.
Dear advisors,
If something has made the Roman Empire in the past, is the law. This has to be the standard for the Byzantine Empire.
That is why I consider it is necessary to create a new set of laws that make a true impact on the Empire. In recent times, people have found ways to break the law and diminish their commitment to maintaining the Empire as it is: a great kingdom.
We new a new code of laws that brought back the discipline and respect we use to have. That is why I need your counseling and experience to create this new legislation that is going to serve us to instill the proper discipline, tolerance, and respect to maintain order in the Empire.
the principles this law code is based on are universal and aimed at the constant improvement of our society.
I ask you to consider a series of laws focused on preventing and punish crime, laws about property, respect for the elderly, women, and children, and laws that promote solid religious thinking that makes us better.
Thank you counselors for your hard work. We do not have much time. So I invite you to start working on these laws in order to have them ready in our next counseling meeting in two months.
Your majesty
Emperor Justinian