Which verses speak about the Battle of Uhud, and what were the reasons for the Muslims' defeat in it?

The verses related to the Battle of Uhud are found in Surat Al-Imran, from verse 121 to a little before the end of the surah (definition). The reason for the Muslims' defeat in the battle was their disobedience to the command of the Prophet, peace and blessings be upon him. Allah wanted to show them the evil consequences of disobedience and failure, so what befell them was due to that ill-omen. Allah, the Almighty, said: (And Allah had certainly fulfilled His promise to you when you were killing them by His permission until when you lost courage and fell into dispute concerning the matter and disobeyed after He had shown you that which you loved. Among you are some who desire this world, and among you are some who desire the Hereafter. Then He turned you away from them to test you. And He has already forgiven you. And Allah is the possessor of bounty for the believers). This teaches Muslims that the dominance of evil over them today is a result of religious transgressions they were warned against.