Sheep Island

Here's a quote from a book I've been reading for school. Actually it's more like a section of the book, not a quote...
I'll let it speak for itself.

"In a dream I found myself on an island -Sheep Island. Across the island sheep were scattered and lost. Soon I learned that a forest fire was sweeping across from the opposite side. It seemed that all were doomed to destruction unless there were some way of escape. Although there were many unofficial maps, I had a copy of the official map and there discovered that indeed there is a bridge to the mainland, a narrow bridge, built, as was said, at incredible cost.
My job, I was told, would be to get the sheep across that bridge. I discovered many shepherds herding the sheep who were found and seeking to corral those who were within easy access to the bridge. But most of the sheep were far off and the shepherds seeking them few. The sheep near the fire knew they were in trouble and were frightened; those at a distance were peacefully grazing, enjoying life.
I noticed two shepherds near the bridge whispering to one another and laughing. I moved near them to hear the cause of joy in such a dismal setting. "Perhaps the chasm is narrow somewhere, and at least the strong sheep have opportunity to save themselves," said one. "Maybe the current is gentle and the stream shallow. Then the courageous, at least, can make it across." The other responded, "That may well be. In fact, wouldn't it be great if this proves to be no island at all? Perhaps it is just a peninsula and great multiudes of sheep are already safe. Surely the owner would have provided some alternative route." And so they relaxed and went about other business.
In my mind I began to ponder their theories: Why would the owner have gone to such great expense to build a bridge, especially since it is a narrow bridge, and many of the sheep refuse to cross it even when they find it? In fact, if there is a better way by which many will be saved more easily, building the bridge is a terrible blunder. And if this isn't an island, after all, what is to keep the fire from sweeping right across into the mainland and destroying everything? As I pondered these things I heard a quiet voice behind be saying, "There is a better reason than the logic of it, my friend. Logic alone could lead you either way, Look at your map."
There on the map, by the bridge, I saw a quotation from the first undershepherd, Peter: "For neither is there salvation in any other, for there is no other way from the island to the mainland whereby a sheep may be saved." And then I discerned, carved on the old rugged bridge itself, "I am the bridge. No sheep escapes to safety but by me."
In a world in which nine of every ten people is lost, three or four have never heard the way out, and one of every two cannot hear, the church sleeps on. "How come?" Could it be we think there must be some other way? Or perhaps we don't really care that much."
-Robertson Mcquilkin