3 That love between man and woman which is neither planned nor willed, but somehow imposes itself upon human beings, was called eros by the ancient Greeks. Let us note straight away that the Greek Old Testament uses the word eros only twice, while the New Testament does not use it at all: of the three Greek words for love, eros, philia (the love of friendship) and agape , New Testament writers prefer the last, which occurs rather infrequently in Greek usage. As for the term philia , the love of friendship, it is used with added depth of meaning in Saint John's Gospel in order to express the relationship between Jesus and his disciples. The tendency to avoid the word eros , together with the new vision of love expressed through the word agape , clearly point to something new and distinct about the Christian understanding of love. In the critique of Christianity which began with the Enlightenment and grew progressively more radical, this new element was seen as something thoroughly negative. According to Friedrich Nietzsche, Christianity had poisoned eros , which for its part, while not completely succumbing, gradually degenerated into vice. Here the German philosopher was expressing a widely-held perception: doesn't the Church, with all her commandments and prohibitions, turn to bitterness the most precious thing in life? Doesn't she blow the whistle just when the joy which is the Creator's gift offers us a happiness which is itself a certain foretaste of the Divine?
Source: Deus Caritas Est (Vatican.va)