9/15/2011. Basic Ideas of Islam . There is but one God, Allah . He rules over all both those who accept him and those who do not.The Last and Greatest Prophet of Allah is MuhammedAllah insists that all conform. His rules of obedience are the Koran, which He revealed to MuhammedThere will be a Last Judgement. We will all go to either heaven or hellAll Men are brothers in Allah\'s eyes and have a duty to care for one another.