Surah Al-Imran ( The Famiy of Imran ) - Aya 165

Why [is it that] when a [single] disaster struck you [on the day of Uhud], although you had struck [the enemy in the battle of Badr] with one twice as great, you said, \"From where is this?\" Say, \"It is from yourselves.\" Indeed, Allah is over all things competent.