Civil law has command over the outward man but not from an authority in and of itself. Its authority, as Junius states, “proceed[s] by reason from those other preceding laws,” namely, the natural law.7 Hence, it is a derived authority, and so laws are just only if they command what proceeds from the natural law. This derivative character is precisely why such laws bind our conscience to them. As Aquinas said, “[Human] laws . . . have the power of binding conscience, from the eternal law whence they are derived [via natural law].”
