Sa'id b. Jubair reported

I said to Ibn Abbas that Nauf al-Bikali was of the opinion that Moses ﷺ, the Apostle of Bani Isra'il, was not the same who accompanied Khadir, whereupon he said: The enemy of Allah tells a lie. I heard Ubayy b. Ka'b say: Moses ﷺ stood up to give sermon to the people of Isra'il. He was asked as to who amongst the people has the best knowledge, whereupon he said: I have the best knowledge. Thereupon Allah was annoyed with him that he did not attribute (the best knowledge) to Him. He revealed to him: A servant amongst My servants is at the junction of two rivers who has more knowledge than yours. Moses said: How can I meet him? It was said to him: Carry a fish in the large basket and the place where you find it missing there you will find him. Thereupon Moses proceeded forth along with a young man (Yusha'). Joshua b. Nun and Moses ﷺ put the fish in the basket and there went along with him the young man (Yusha') until they came to a certain rock and Moses and his companion went to sleep and the fish stirred in that basket and fell into the ocean and Allah stopped the current of water like a vault until the way was made for the fish. Moses and his young companion were astonished and they walked for the rest of the day and the night and the friend of Moses forgot to inform him of this incident. When it was morning, Moses ﷺ said to the young man: Bring for us the breakfast for we are dead tired because of this journey, and they did not feel exhausted until they had passed that place where they had been commanded (to stay). He said: Don't you know that when we reached the Sakhra (rock) I forgot the fish and nothing made me forget it but Satan that I could not remember it? How strange is it that the fish found a way in the river? Moses said: That was what we had been aiming at. Then both of them retraced their steps until they reached Sakhra; there they saw a man covered with a cloth. Moses greeted him. Khadir said to him: Where is as-Salam in our country.? He said: I am Moses, whereupon he (Khadir) said: You mean the Moses of Bani Isra'il? He said: Yes. He (Khadir) said: You have a knowledge out of the knowledge of Allah which in fact Allah imparted to you and about that I know nothing and I have knowledge out of Allah's knowledge which He imparted to me and about that you do not know. Moses ﷺ said to him: May I follow you so that you may teach me that with which you have been taught righteousness. He said: You will not be able to bear with me; how you will be able to bear that about which you do not know? Moses said: Thou wilt find me patient, nor shalt I disobey you in aught. Khadir said to him: If you were to follow me, then do not ask me about anything until I myself speak to you about it. He said: Yes. So Khadir and Moses set forth on the bank of the river that there came before them a boat. Both of them talked to them (the owners of the boat) so that they might carry both of them. They had recognised Khadir and they carried them free. Khadir thereupon took hold of a plank in the boat and broke it away. Moses said: These people have carried us without any charge and you attempt to break their boat so that the people sailing in the boat may drown. This is (something) grievous that you have done. He said: Did I not say that you would not bear with me? He said: Blame me not for what I forgot and be not hard upon what I did. Then both of them got down from the boat and began to walk along the coastline that they saw a boy who had been playing with other boys. Khadir pulled up his head and killed him. Moses said: Have you killed an innocent person who is in no way guilty of slaying another? You have done something horrible. Thereupon he said: Did I not say to you that you will not be able to bear with me? He (Moses) said: This (act) is more grievous than the first one. He (Moses) further said. If I ask you about anything after this, keep not company with me, then you would no doubt find (a plausible) excuse for this. Then they both walked on until they reached the inhabitants of a village. They asked its inhabitants for food but they refused to entertain them as their guests. They found in it a wall which had been bent on one side and was about to fall. Khadir set it right with his own hand. Moses, said to him: It is the people to whom we came but they showed us no hospitality and they did not serve us food. If you wish you can get wages for it. He (Khadir) said: This is the parting of ways between me and you. Now I wish to reveal to you the significance of that for which you could not bear with me. Allah's Messenger (ﷺ) said. May Allah have mercy upon Moses! I wish if Moses could show patience and a (fuller) story of both of them could have been told. Allah's Messenger (ﷺ) said that the first thing which Moses said was out of forgetfulness. Then there came a sparrow until it perched on the wall of the boat and took water from the ocean. Thereupon, Khadir said: My knowledge and your knowledge in comparison with the knowledge of Allah is even less than the water taken by the sparrow in its beak in comparison to the water of the ocean, and Sa'id b. Jubair used to recite (verses 79 and 80 of Sura Kahf) in this way: There was before them a king who used to seize every boat by force which was in order, the boy was an unbeliever.