Aslan

The Lion, whose eyes never blinked, stared at the animals as hard as if he was going to burn them up with his mere stare. And gradually a change came over them. The smaller ones - the rabbits, moles and such-like grew a good deal larger. The very big ones - you noticed it most with the elephants - grew a little smaller. Many animals sat up on their hind legs. Most put their heads on one side as if they were trying very hard to understand. The Lion opened his mouth, but no sound came from it; he was breathing out, a long, warm breath; it seemed to sway all the beasts as the wind sways a line of trees. Far overhead from beyond the veil of blue sky which hid them the stars sang again; a pure, cold, difficult music. Then there came a swift flash like fire (but it burnt nobody) either from the sky or from the Lion itself, and every drop of blood tingled in the children's bodies, and the deepest, wildest voice they had ever heard was saying:

"Narnia, Narnia, Narnia, awake. Love. Think. Speak. Be walking trees. Be talking beasts. Be divine waters."

Chapter 9: the creation of narnia, page 70, the Magician’s nephew.

It was of course the Lion's voice. The children had long felt sure that he could speak: yet it was a lovely and terrible shock when he did.

Out of the trees wild people stepped forth, gods and goddesses of the wood; with them came Fauns and Satyrs and Dwarfs. Out of the river rose the river god with his Naiad daughters. And all these and all the beasts and birds in their different voices, low or high or thick or clear, replied:

"Hail, Aslan. We hear and obey. We are awake. We love. We think. We speak. We know."

Chapter 10, the first joke and other matters, page 71, the magician's nephew.