Al-Anfal 8:10

Wama jaAAalahu Allahu illabushra walitatma-inna bihi quloobukum wama annasruilla min AAindi Allahi inna Allaha AAazeezunhakeem

And Allāh made it not but good tidings and so that your hearts would be assured thereby. And victory is not but from Allāh. Indeed, Allāh is Exalted in Might and Wise.

And Allah has made it (the promise) merely to give you a good news, and so that your hearts might be at rest thereby. And the help is from none but Allah. Surely, Allah is Mighty, Wise.