Why is the number 3 significant with Dante Alighieri?

The number 3 is everywhere in Dante Alighieri's Divine Comedy. For one thing, the poem itself is structured according to the rhyme scheme terza rima, which uses stanzas of three lines that employ interlocking rhymes (aba bcb cdc, etc.). Additionally, there are nine circles of Hell (three multiplied by three), Satan has three faces, and three beasts (a lion, a leopard, and a wolf) threaten Dante at the beginning of the Inferno. There are many more examples of three, but the overall important thing to understand is that the number three largely governs the structure of Dante's poem. Indeed, you can think of the number three as the scaffolding on which the rest of the poem's content is hung. This number is significant because three is a central number in the Judaeo-Christian tradition, especially in terms of the Trinity (Father, Son, and Holy Spirit). As such, just as the whole of the Christian world is governed by a three-in-one God, Dante's poem is governed by the number three. Thus, Dante's obsession with the number three mirrors the prevalence of three in the Christian tradition.