Narrated It was narrated that Marwan bin al-Hakam said:
We were walking with ‘Uthman (رضي الله عنه) and saw a man entering ihram for both .`Uthman (رضي الله عنه) said Who is this? They said: `Ali. He said: Do you not know that I have forbidden this? He said: Yes, but I will not give up the advice of the Messenger of Allah (ﷺ) for your opinion.
A man asked “Ali (رضي الله عنه) about (sacrificing) a cow. He said: (it may be sacrificed) on behalf of seven people. He said: (What about a cow with) a broken horn? He said. It doesn`t matter. He said: (What if it is) lame? He said: If it can reach the place of sacrifice, then slaughter it. The Messenger of Allah (ﷺ) commanded us to examine the eyes and ears.