question #2 Sahih al-Bukhari 31, Book 2, Hadith 24 : Why is the intention behind an action significant in determining its moral and spiritual consequences in Islam?

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 Messenger (ﷺ)
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 Messenger (ﷺ)! It is all right for the murderer but what
about the murdered one?’ Allah’s Messenger (ﷺ) replied, “He surely had the
intention to kill his companion.”