Hadiths 1.30 and 1.31

1.30:
Narrated Al−Ahnaf bin Qais: While I was going to help this man
(`Ali Ibn Abi Talib), Abu Bakra met me and asked, "Where are
you going?" I replied, "I am going to help that person." He
said, "Go back for I have heard Allah's Apostle saying, 'When
two Muslims fight (meet) each other with their swords, both
the murderer as well as the murdered will go to the
Hell−fire.' I said, 'O Allah's Apostle! It is all right for
the murderer but what about the murdered one?' Allah's Apostle
replied, "He surely had the intention to kill his companion."

1.31:
Narrated `Abdullah: When the following Verse was revealed: "It
is those who believe and confuse not their belief with wrong
(worshipping others besides Allah.)" (6:83), the companions of
Allah's Apostle asked, "Who is amongst us who had not done
injustice (wrong)?" Allah revealed: "No doubt, joining others
in worship with Allah is a great injustice (wrong) indeed."
(31.13)