Al-Anfal - 8:13

ذَلِكَ بِأَنَّهُمْ شَآقُّواْ اللّهَ وَرَسُولَهُ وَمَن يُشَاقِقِ اللّهَ وَرَسُولَهُ فَإِنَّ اللّهَ شَدِيدُ الْعِقَابِ
[8:13]
This is because they acted adversely to Allah and His Messenger; and whoever acts adversely to Allah and His Messenger-- then surely Allah is severe in requiting (evil).
This because they contended against Allah and His Messenger: If any contend against Allah and His Messenger, Allah is strict in punishment.
That is because they opposed Allah and His messenger. Whoso opposeth Allah and His messenger, (for him) lo! Allah is severe in punishment.