Book excerpt: In The Burhān Mohammad Hijab analyses Ibn Sīnā's argument for the existence of God. Regards as being most invulnerable to any type of counterattack, Ibn Sīnā's Burhān argument postulates that a world with only contingent existences is inconceivable, as a contingent existence cannot cause itself. Ibn Sīnā argues that the only way to explain the existence of anything is to postulate the existence of a uncaused necessary being, or a wājib al-wujūd ('necessary existence'). However, despite its impact, the Burhān has not been packaged for apologetic use for a modern audience. Hijab's novel contribution to the discourse surrounding God's existence is found in his re-articulation of this argument for theists attempting to make the case for religion to atheist audiences. Using the Burhān as his guide, Hijab provides his own proofs for the necessary existence of God and answers some of the most prominent objections. Hijab applies the arguments for a necessary being by referring to potential pastoral and apologetic settings using two fictitious characters, Richard and Betty.