Many religions and philosophies profess that "God is loving." Loving is something God does, it's one of his traits. But Christianity's strange and startling claim is that God is love. It's not what he does, it's who he is. Love always requires three things: a lover, a beloved, and the love shared between them. This is what we mean when we say God is a Trinity—Father, Son, and Holy Spirit, one God in three persons.