Jesper Who Herded the Hares
The motif of herding hares is a common fairy tale theme. Another tale featuring it is The Three May Peaches. This tale, and The Griffin, also feature the test of truthfully telling what the character is carrying.
A king of a kingdom so small he could see every border from the towers on his castle, still was proud of it. Having a single daughter, he wished her to marry a man fit to be king. He declared that whoever brought him twelve of the finest pearls (to ensure the wooer was rich) and could perform certain tasks would marry her. Many princes and merchants brought the pearls but failed the tasks, and many tried false pearls and were turned away more quickly.
A fisherman had three sons: Peter, Paul, and Jesper. One day he caught three dozen oysters, each of which had a fine pearl. It was decided that each son would have his chance to win the princess. On the way, Peter met the King of the Ants, who was battling the King of the Beetles and had been worsted; he asked for Peter's help, and Peter said he was too busy. Then he met an old woman, who asked what he was carrying; he said cinders, she said that, very well, it was cinders, and when he got to the castle, the pearls turned into cinders. He did not tell what had happened when he came home. Paul tried, and met the same fate. Jesper tried; he helped the king of the ants, who won the field with him, and told the old woman of his pearls. The old woman begged some food from him, since he could eat at the castle. He handed over his entire lunch. The old woman called him back and gave him a whistle that would bring back what he had lost.
The king was not pleased with such a son-in-law. He had a sack each of wheat, barley, oats, and rye mixed together and told Jesper he had to sort them in a day. The ants did it for him.
Then he was set to herd a hundred hares. Using the whistle, he kept them together. The king heard of it and resolved to stop him. A shabby girl begged for a hare to feed for guests; finally, Jesper agreed to give her one in return for a kiss, but then he whistled it back. A stout old woman, in peasant dress, came next. He agree to give her one if she would tiptoe about him cackling like a hen, and then he whistled it back. An fat old man in a royal groom's livery came, and Jesper agreed to give him one if he stood on his head, and then whistled it back.
The next day, the king set out a tub and said that Jesper must fill it with undoubted truths, and he would judge when that was. Jesper told about the girl, and that she was the princess; then about the woman, and that she was the queen; then about the old man -- and the king declared that the tub was full, so Jesper married the princess, and the king decided he would be a good king if he looked after the people as well as he looked after the hares.
- Andrew Lang, The Violet Fairy Book, "Jesper Who Herded the Hares"