What is the source of this hadith regarding angels and the language of the Qur'an?

Sources

• ✓ Al-Kafi 3:71

  Shia

  Al-Kafi · Book 3, Hadith 71

  I came to al-Ridha (peace be upon him) asking about Tawhid (Divine Unity). He dictated to me: 'Praise be to Allah, the Originator of things by creation and the Initiator of them by His power, not from anything so that invention fails, and not due to cause that innovation be valid. He created what He wished however He wished, absolutely unique in this, to manifest His wisdom and the reality of His Lordship. The intellects cannot grasp Him, neither do imaginations reach Him, nor can the eyes perceive Him nor does any measure encompass Him. Expression and perception tire before Him. He is hidden without veil and concealed without cover; He is known without sight, described without shape, and characterized without body. There is no god but Allah, the Great, the Exalted. — OR — The Prophet (peace be upon him and his family) said: A non-Arab among my nation recites the Qur’an in his foreign tongue, yet the angels raise it in Arabic. — OR — I was present at the death of one of the two sons of Sabor, who were known for their piety and humility. One of them, I believe it was Zakariya ibn Sabor, fell ill. I visited him at his death, and he stretched out his hand and said, 'My hand has turned white, O Ali.' Then I went to Abu Abdullah (peace be upon him) with Muhammad ibn Muslim. When I left his presence, I thought Muhammad would inform him of the news of the man. A messenger followed me back, so I returned to him. He said, 'Tell me about this man whom you attended at death. What did you hear him say?' I said, 'He stretched out his hand and said, "My hand has become white, O Ali."' Abu Abdullah said, 'By Allah, he saw it; by Allah, he saw it; by Allah, he saw it.' — OR — I asked about the verse: 'And whoever enters it shall be safe.' He said: If a thief steals outside Mecca or commits a crime against himself and then flees to Mecca, he is not caught while in the sanctuary until he leaves it. However, he is prevented from the market, neither bought from nor associated with, until he leaves; then he is caught. If he commits the crime inside the sanctuary, he is apprehended and punished there. — OR — Amir al-Mu'minin (peace be upon him) said: "Marry a large-eyed, dark-complexioned, physically weak, and thick-set woman. If you dislike her, the dowry is my responsibility." — OR — The manumission granted under compulsion is not to be considered valid manumission. — OR — I asked him where is the place the one who commits fornication with a close relative is struck by the sword? He said: He is struck on the neck, or he said: on the throat.