When Musa came back to his people after meeting al-Khidhr, Harun asked him about the knowledge Musa had obtained from al-Khidhr and about the wonders he had observed in the river. Musa said, “al-Khidhr and I were standing on the banks of the river when suddenly we saw a bird come to the river from the air, take a drop of water in its beak and throw it in the east, then it threw another drop towards the west, then one drop towards the sky and one to the earth. Then it took a drop from the sea and threw it back in the river. I asked al-Khidhr the cause of these actions of the bird, but al-Khidhr did not know. Suddenly I saw a hunter fishing on the banks of the river. He looked towards me with surprise and asked, ‘What makes you wonder?’ I said, ‘This bird’s gesture makes us wonder.’
He said, ‘I am only a hunter and I know the cause of these actions of the bird. How is it that despite being Messengers of Allah you two do not comprehend it.’ We said, ‘We know only that which Allah has taught us.’ The hunter said, ‘This is a bird which is known in the river by the name of ‘Muslim’ because it utters ‘Muslim” whenever it twitters. What it points out by its gestures is that Allah will send a Messenger after you whose followers will rule over the east and the west throughout the world, will go up in the sky and will be buried in the ground and that in the sight of that Prophet the knowledge of other scholars will be just like a drop of water of this river (in proportion) and his knowledge will reach his cousin and his legatee as heritage.’ O Harun! At that time, our knowledge felt little in our own eyes and then the hunter disappeared. So we understood that he was an angel sent by Allah to discipline us.”