Surah An Nisa. Ayats 71 — 80
All you who believe! Be cautious and only venture out (into dangerous places) either in groups or all together.  Indeed, there are some among you who try to lag behind (when you’re on the road). If misfortune befalls you, they say, “Allah was gracious to us by not keeping us among them to witness (their misfortune).”  However, if some good fortune befalls you from Allah, he’ll say, as if he didn’t know you closely, “Oh, how I wish I could’ve been there with them because I would’ve had a great time!” 
Let them fight in the cause of Allah, those who sell the life of this world for the life of the Hereafter. To the one who fights in the cause of Allah, whether he’s killed or achieves victory, We’re soon going to give him a great reward.  And why shouldn’t you fight in the cause of Allah and in the cause of those who, being weak, are mistreated: the men, women and children whose only cry is, “Our Lord! Deliver us from this land whose people are oppressors.
Send us someone from You who will protect us, and send us someone from You who will help!” (75) Those who have faith (in Allah) fight in the cause of Allah, while those who cover over (their ability to have faith) fight in the cause of falsehood, so fight against the allies of Satan, for truly Satan’s plan is weak. (76)
Haven’t you seen the people who were told to restrain their hands (from fighting) and who were counseled instead (to concentrate on) establishing prayer and giving in charity? When the order finally came for them to fight, a bunch of them became more scared of people than they were scared of Allah!
“Our Lord!” they cried out. “Why have You ordered us to fight? Won’t you postpone it for us, at least for a while longer?” Say to them, “The enjoyment of this world is indeed short.
The next life is better for the one who is mindful (of Allah). You won’t be wronged by as much as the string of a date seed!  Wherever you are, death will find you, even if you lodge yourselves in mighty towers!”
Whenever good fortune befalls them, they say, “This is from Allah,” but if they’re ever hit with misfortune they say, “This is all your fault, (Muhammad).” Say to them, “Every (outcome) is from Allah.”
So what is it with these people that they don’t understand a single phrase?  Any good that comes your way is from Allah, while any misfortune that befalls you is your own fault. We sent a messenger to people, and Allah is enough of a witness for that!  Whoever obeys the Messenger obeys Allah, while whoever turns away (from you, Muhammad,) well, We didn’t send you to be their caretaker. 
Translation: Yahiya Emerick
Background behind versus:
Background on verses 71-73: Due to the constant raiding and attacks of the pagans in the countryside, the Muslims were discouraged from moving about in the land alone. When the Prophet organized patrols or sent out skirmishers to clear an area of raiders, some men of Medina would go absent without leave or otherwise conveniently get “lost” to avoid any potentially dangerous situations. If the patrols were successful and drove off pagan raiders, capturing booty in the process, these laggards would lament their loss of material gains. That is the subject matter of this passage.
Background on verses 74-75: Even though the Muslims had migrated to the safe haven of Medina, Muslims were not allowed yet to defend themselves from the Meccans, who harassed, tortured and killed Muslims with impunity both within Mecca and in the countryside. This quoted supplication in verse 75 was what the Muslims were asking of Allah. This passage was then revealed, giving Muslims permission to defend themselves.
Background on verses 77-79: This passage was revealed with regards to several of Prophet Muhammad’s ( Peace be upon him) followers who were severely persecuted in the early days of the Meccan period. At that time they were begging Prophet Muhammad ( Peace be upon him) to let them fight back against the idol-worshippers who would daily assault them in the streets and vandalize their property. He always refused their request and counseled them to be patient and engage in more religious activity. After the Migration to Medina, the order finally came to fight the Meccans, and many of these same men became reluctant to go to war.