/summa/FS/FSVI/FS_Q91:
We must now consider the various kinds of law: under which head there are six points of inquiry:
(1) Whether there is an eternal law?
(2) Whether there is a natural law?
(3) Whether there is a human law?
(4) Whether there is a Divine law?
(5) Whether there is one Divine law, or several?
(6) Whether there is a law of sin?