2. Phrase. (literary) A series of miserable events will eventually lead to a happier outcome. ¹
3. Phrase. (religion) The Biblical story of the fall of Adam and Eve and the loss of the Garden of Eden, known theologically as the source of original sin - meaning that this loss of innocence was a fortunate fall because of the good that would come from it, that is, Christian redemption and the eventual hope of Heaven. ¹
¹ Source: wiktionary.com