Whoever I am the patron of, Ali is his patron

Abdullah bin Buraydah al-Aslami narrates from his father: I was walking with my father when he passed by some people who were disparaging Sayyiduna Ali (may Allah be pleased with him) and saying (unseemly) things about him. My father stood up and said: I too used to be displeased with Ali (may Allah be pleased with him) and had something against him in my heart. I was with Khalid bin al-Walid (may Allah be pleased with him) in an army where we obtained spoils of war, and Ali (may Allah be pleased with him) took a slave girl from the khums for himself. There was also some ill-feeling between Ali (may Allah be pleased with him) and Khalid (may Allah be pleased with him). So Khalid said (to me), since he knew what was in my heart against Ali: This is your chance; go to the Prophet (peace and blessings be upon him) and mention this matter to him. So I came to the Prophet (peace and blessings be upon him) and related the whole incident to him. I used to keep my head lowered while speaking. When I had mentioned the army and then Ali (may Allah be pleased with him), I raised my head and saw that the neck veins of the Messenger of Allah (peace and blessings be upon him) had turned red (with anger). He (peace and blessings be upon him) said: "Whoever I am the wali (patron/friend) of, Ali is also his wali." After that, the resentment that was in my heart against him went away.
This hadith is sahih (authentic) on the condition of the two Shaykhs (Bukhari and Muslim), but they did not record it with this wording. Imam Bukhari recorded it in abridged form, but in this chapter this narration of Abu Awanah, through al-A'mash, is the most authentic.

It is narrated from Sayyiduna Buraydah (may Allah be pleased with him) that he passed by a gathering, and then he related the whole incident in detail, similar to the previous hadith.