What makes Voltaire's "of universal tolerance" satirical

Voltaire's Universal Tolerance.

Satire is a type of genre in literature which basically draws attention to wider issues of society and which uses harsh language to ridicule the individuals or society itself to bring out the necessary changes and improvement.

'A Treatise on tolerance' is a literary work which was authored by Voltaire in the year 1763. The work is satirical mainly because Voltaire claims for tolerance where he spoke against the various superstitious practices and religious fanaticism held by people. Voltaire was even jailed because of his satirical work, but he believed that every person should have freedom of speech.