Why did Thomas Hobbes oppose separating church power from state power?

Thomas Hobbes opposed the separation of church and state because he believed that divided authority inevitably leads to instability, conflict, and the breakdown of the social contract necessary for peace.12

In his political philosophy, Hobbes argued that the sovereign must hold absolute power to effectively maintain order and prevent the "war of all against all" that characterizes the natural state of humanity. He viewed the separation of powers—whether between branches of government or between civil and ecclesiastical authorities—as a dangerous dilution of this necessary control.312

Specifically, Hobbes maintained that:
* Unified Authority: The sovereign must be the supreme commander of the army, the final interpreter of law, and the supreme interpreter of scripture.31
* Prevention of Factionalism: He believed that independent church power allowed "power-hungry" priests and popes to challenge legitimate civil authority, which he identified as a primary cause of civil war.1
* Subordination of the Church: He argued that churches possess no authority except that which is granted by the civil sovereign, ensuring that religious institutions cannot undermine the state's mandate to provide security.31