In this sermon, the main thrust of St Paul's argument is that love never fails. The passage is a strange choice for a funeral as it doesn't discuss death, yet comes shortly before a famous passage on the subject: "oh Death, where is thy sting?"
Being and Nothingness is the name of a classic Existentialist book by Jean-Paul Sartre. In his work, Sartre sought to explore the idea that an individual's existence is both prior to and separate from their existence. Sartre wrote Being and Nothingness in 1940-41, when he was a prisoner of war in France; he was very much influenced by the German philosopher Martin Heidegger's Being and Time.