"With similes, our delight comes from the containment of seeing only the images given us by the poet and no others. . . ; [w]ith metaphor, we range farther." (Suzanne Clark, in The Roar On the Other Side)
Scripture is full of metaphors. Jesus says he is the door, the good shepherd, the light, the cornerstone, and so on, enough to confound any literalist on Scripture! In fact, there are more metaphors than similes: the gospel is not fenced in but runs wild, uncontained. We ask how is he the good shepherd, how is he the door, and our minds run free with the associations, bounded only by other portions of Scripture as impressed on our hearts and minds by the Holy Spirit.
I am a blade of grass, you a grain of sand among many, and yet we are stars that shine, a little lower than the angels -- friends of God. The same door that opens to the Kingdom of God, the one that bears such a positve image in our minds of a welcoming knock, an invitaton to come in, will one day slam tightly shut and bar the way to those who reject God. But who slams it? The ones who reject God.
Clark says that "[t]he ability to make associations, to think in metaphors and similes, is evidence of God's image in us. We think analogically, instinctively, because that is who we are. We read of God as Father, and associations with earthly fathers spring to mind. We say God is good and must immediately associate the abstraction of that word with, say, a father's love, a selfless person like Mother Teresa or Aunt Flora on your father's side once removed who never, never thinks of herself. Or maybe even the faithful, loving dog who always returns though neglected and mistreated by his master. That word "good" is unfenced, set free, encompassing everything that is the antithesis of bad.
There's another thing she notes about such imaginative language: "Imaginative language --- poetry --- trains the mind in faith. For what is faith but divine realities we can only imagine, 'the substance of things hoped for, the evidence of things not seen' (Heb. 11:1)." I never thought of it that way. Metaphorming --- the ability to make associations between things --- is essential to a growing faith, a realization of the richness and otherworldly and fulsome character of the Good News.
"When Jesus proclaims, 'I am the Bread of life,' he removes all our fences of seeing. He is entirely bread --- nourishing, flavorful, essential. Rising and resurrection are in the loaf, too. It is bread enough for the whole world, and of this Bread we must eat or perish. 'Unless you eat the flesh of the Son of Man and drink His blood, you have no life in you.' (John 6:53). Is this metaphor? Is this not mystery? Let us keep silent."