Why did Leviathan offend many of Thomas Hobbes’s contemporaries?

Thomas Hobbes’s Leviathan (1651) deeply offended many of his contemporaries for several reasons, primarily concerning his views on human nature, religion, and political authority.

• Accusations of Atheism and Cynicism: Hobbes was widely accused of atheism and of "maligning human nature." By rejecting the classical and Thomist concepts of a transcendent law of nature and arguing that humans are naturally antisocial, competitive, and driven by fear and vanity, he challenged the prevailing moral and religious frameworks of his time.1
• Controversial Political Implications: Hobbes suggested that a subject has the right to abandon a ruler who can no longer provide protection. This idea caused serious offense to the advisers of the exiled Prince Charles, as it undermined the traditional, absolute loyalty expected toward a monarch.2
• Ecclesiastical Authority: Hobbes argued that churches possess no authority independent of the civil sovereign. He maintained that the sovereign is the supreme interpreter of scripture and has authority over any national church, which alienated religious leaders and bishops who viewed his work as a threat to ecclesiastical independence.342

Ultimately, his work was seen as so dangerous that the House of Commons later investigated Leviathan in the context of legislation against atheism.2