The number three in the Bible represents completeness. That's why Jesus rose on the third day after the Crucifixion -- his transformation was complete. It's why Elijah stretched himself on the dead child three times, why Jonah was in the belly of the fish for three days, why the Lord called Samuel three times, and many more. It's also reflected in the fact that there are three levels of heaven, three levels of hell, three levels to human life and, ultimately, three aspects of the Lord Himself: Father, Son and Holy Spirit.

48. Those of them who are in the heaven of the Mohammedans have only one wife, having rejected more. For there is a Mohammedan heaven distinct from the Christian heaven. But those who eventually, as many do, acknowledge the Lord as one with the Father are separated and are in heavens which communicate with the Christian heavens; and they have conjugial love.