question #3 Sahih Muslim 359b, Book 3, Hadith 122 : What is the significance of eyewitness accounts in the transmission of hadiths?

I was with Ibn ‘Abbas, and Ibn ‘Abbas saw the Messenger of Allah (ﷺ) doing like this, and it is also said that the words are: He (the Holy Prophet) offered prayer; and the word” people” is not mentioned.