The Family Of Imran - 3:13
There is a lesson for you in the two armies that met. One army was fighting in the way of Allah and the other was disbelieving. With their eyes they saw them (the believers) as twice their number. Allah supports whom He wills with victory. In this is a lesson for those who have insight.
In whose cause do the disbelievers fight?
The Women/4:76
Those who believe fight in the way of Allah. And the disbelievers fight in the way of the transgressors and despots. So fight the friends of Satan; Satan´s plan is weak.