The Family Of Imran - 3:103 Hold fast to the rope of Allah, and do not differ. Remember the favor of Allah upon you. When you were enemies, He united your hearts and by His favor you became brothers. You were on the edge of a pit of fire and He saved you from it. This is how Allah explains His verses so that you may be guided.
Related:
The Cow/2:27 Those who, after pledging allegiance to their covenant with Allah, break it, cut off what Allah has commanded to be joined, and make corruption in the earth. They are the losers.

The Family Of Imran/3:103 Hold fast to the rope of Allah, and do not differ. Remember the favor of Allah upon you. When you were enemies, He united your hearts and by His favor you became brothers. You were on the edge of a pit of fire and He saved you from it. This is how Allah explains His verses so that you may be guided.

The Thunder/13:21 Those who unite what Allah has commanded them to unite, and they honor their Lord and fear the evil Reckoning.
The Thunder/13:25 Those who break their covenant after their promise to Allah, those who do not unite what Allah has commanded to be united, and those who make mischief in the earth have deserved the curse and for them is an evil consequence.

Muhammad/47:22 So if you should come to power, you would make corruption in the earth and break the ties of kinship?

The Apartments/49:10 The believers are brothers. Set things right between your brothers. Honor Allah so that you may be merciful.