How did Thomas Hobbes define justice after the creation of a sovereign power?

For Thomas Hobbes, justice is not a natural concept but one that only becomes possible after the creation of a sovereign power.12

In the state of nature, where individuals exist in a "war of all against all," moral ideas like justice have no meaning because there is no impartial authority to enforce agreements. Hobbes argued that justice is essentially the keeping of valid covenants or promises. However, because humans are rational and self-interested, they will only keep their promises if they are certain others will do the same.123

Once a social contract is established and a sovereign—the Leviathan—is empowered to punish those who breach their agreements, justice becomes possible. Under this system, acting justly is rational because the sovereign ensures that those who fail to keep their agreements face suitable punishment. Consequently, it is considered unjust for a subject to renege on the social contract or challenge the sovereign's laws, as the individual has already agreed to delegate the judgment of collective security to that authority.123