LITERAL /CONTEXTUAL MEANING OF QURAN 3: 149-151
(149. O you who believe! If you obey those who disbelieve, they will send you back on your heels, and you will turn back as losers.) (150. Nay, Allah is your protector, and He is the best of helpers.) (151. We shall cast terror into the hearts of those who disbelieve, because they joined others in worship with Allah, for which He sent no authority; their abode will be the Fire and how evil is the abode of the wrongdoers.)
During the battle of Uhud, muslims were defeated because they disobeyed Prophet Muhammed (SAW). Allah revealed these verses to Prophet (SAW) to warn His believing servants against obeying the disbelievers and hypocrites, because such obedience leads to utter destruction in this life and the hereafter. Allah also commands the believers to obey Him alone, take Him as their protector, seek His aid and trust in Him.
Allah next conveys the good news that He will put fear of the Muslims, and feelings of subordination to the Muslims in the hearts of their disbelieving enemies, because of the Kufr (disbelief) and Shirk (polytheism). And Allah has prepared torment and punishment for them in the hereafter.
FURTHER EXPLANATION FROM SAHIH HADITH
Al-Bukhari recorded that Al-Bara' said, "We met the idolators on that day (Uhud) and the Prophet appointed `Abdullah bin Jubayr as the commander of the archers. He instructed them, `Retain your position, and if you see that we have defeated them, do not abandon your positions. If you see that they defeated us, do not rush to help us.' The disbelievers gave flight when we met them, and we saw their women fleeing up the mountain while lifting up their clothes revealing their anklets and their legs. So, the companions (of `Abdullah bin Jubayr) said, `The booty, the booty!' `Abdullah bin Jubayr said, `Allah's Messenger commanded me not to allow you to abandon your position.' They refused to listen, and when they left their position, Muslims were defeated and seventy of them were killed. Abu Sufyan shouted, `Is Muhammad present among these people' The Prophet said, `Do not answer him.' Then he asked, `Is the son of Abu Quhafah (Abu Bakr) present among these people' The Prophet said, `Do not answer him.' He asked again, `Is the son of Al-Khattab (`Umar) present among these people As for these (men), they have been killed, for had they been alive, they would have answered me.' `Umar could not control himself and said (to Abu Sufyan), `You lie, O enemy of Allah! The cause of your misery is still present.' Abu Sufyan said, `O Hubal, be high!' On that the Prophet said (to his Companions), `Answer him back.' They said, `What shall we say' He said, `Say, Allah is Higher and more Sublime.' Abu Sufyan said, `We have the (idol) Al-`Uzza, and you have no `Uzza.' The Prophet said, `Answer him back.' They asked, `What shall we say' He said, `Say, Allah is our protector and you have no protector.' Abu Sufyan said, `Our victory today is vengeance for yours in the battle of Badr, and in war (the victory) is always undecided and is shared in turns by the belligerents. You will find some of your killed men mutilated, but I did not urge my men to do so, yet I do not feel sorry for their deed.''' Only Al-Bukhari collected this Hadith using this chain of narration. cMuhammad bin Ishaq said that, `Abdullah bin Az-Zubayr narrated that Az-Zubayr bin Al-`Awwam said, "By Allah! I saw the female servants and female companions of Hind (Abu Sufyan's wife) when they uncovered their legs and gave flight. At that time, there was no big or small effort separating us from capturing them. However, the archers went down the mount when the enemy gave flight from the battlefield, seeking to collect the booty. They uncovered our back lines to the horsemen of the disbelievers, who took the chance and attacked us from behind. Then a person shouted, `Muhammad has been killed.' So we pulled back, and the disbelievers followed us, after we had killed those who carried their flag, and none of them dared to come close the flag, until then.''' Muhammad bin Ishaq said next, "The flag of the disbelievers was left on the ground until `Amrah bint `Alqamah Al-Harithiyyah picked it up and gave it to the Quraysh who held it.''