"Please," said the Lamb, "I can't understand. What have we to do with the Calormenes? We belong to Aslan. They belong to Tash. They have a god called Tash. They say he has four arms and the head of a vulture. They kill Men on his altar. I don't believe there's any such person as Tash. But if there was, how could Aslan be friends with him?"
All the animals cocked their heads sideways and all their bright eyes flashed towards the Ape. They knew it was the best question anyone had asked yet.
The Ape jumped up and spat at the Lamb.
"Baby!" he hissed. "Silly little bleater! Go home to your mother and drink milk. What do you understand of such things? But the others, listen. Tash is only another name for Aslan. All that old idea of us being right and the Calormenes wrong is silly. We know better now. The Calormenes use different words but we all mean the same thing. Tash and Aslan are only two different names for you know Who. That's why there can never be any quarrel between them. Get that into your heads, you stupid brutes. Tash is Aslan: Aslan is Tash"
fair use for educational and discussion purposes
The last battle by C.S. Lewis. Copyright 1956 by C.S. Lewis Pte Ltd 1956 Published by HarperCollinsPublishers, Ltd. Hammersmith, London
I wonder if CS Lewis invisioned back in 1956 that in 56 more years Christian preachers would be asserting that Allah, the god who rewards those who kill themselves slaughtering innocents on his altar, would be said to be the same as the God of Israel. That people who question this would be called intolerant and told that they were too stupid to understand the deep things of God. Or when he wrote about Tashlan he suspected one day people would be holding worship services in the name of Chrislam.
It is fitting that this happened in the story right before the final battle of that world and the entrance through a stable door into heaven, where all things were made perfect.