Once upon a time there was a nightingale and a blindworm, each with one eye. For a long time they lived together peacefully and harmoniously in a house. However, one day the nightingale was invited to a wedding, and she said to the blindworm: "I've been invited to a wedding and don't particularly want to go with one eye. Would you be so kind as to lend me yours? I'll bring it back to you tomorrow."
The blindworm gave her the eye out of the kindness of her heart. But when the nightingale came home the following day, she liked having two eyes in her head and being able to see on both sides. So she refused to return the borrowed eye to the blindworm. Then the blindworm swore that she would revenge herself on the nightingale's children and the children of her children. "Well," replied the nightingale, "see if you can find me.
I'll build my nest in the linden,
so high, so high, so high.
You'll never be able to find it,
no matter how hard you try."
Since that time all nightingales have had two eyes, and all the blindworms, none. But wherever the nighingale builds her nest, a blindworm lives beneath it in the bushes and constantly endeavours to crawl up the tree, pierce the eggs of her enemy, and drink them up.