The contrast between the theory and practice of Islamic banking is generally acknowledged by many scholars. After more than three decades in operation, the rapid growth of the Islamic banking industry is, in reality being driven by the application of the debt-like contracts (e.g. murÁbaÎah and ijÁrah) rather than the profit and loss sharing contracts (e.g. muÃÁrabah and mushÁrakah). As the adaptation of the former contracts creates "unauthentic" Islamic financial products, many have questioned their compliance with sharÐÝah principles. The present study analyses this issue by examining the application of muÃÁrabah rules in Malaysian Islamic banking practices. It evaluates the extent to which the current practices fulfil the principles and the ethical framework of the muÃÁrabah contract as propounded by the classical jurists. The study also analyses the justifications of Malaysian sharÐÝah scholars for modification of the doctrine, adapting it to the modern banking business. The study found that the local sharÐÝah scholars have adopted an incoherent legal methodology when making their ijtihÁd. They can be very rigid, concentrating solely on the legal technicality and at the same time be very flexible, adapting an unregulated doctrine of maÒlaÎah. Therefore, some of their resolutions could be seen as contradictory to the rulings found in classical fiqh.