Do not take knowledge in matters of religion-- no matter whether the person giving the knowledge is known or unknown-- unless you have verified it with the Quran's basic principles of:

** Worship Allah alone and seek help from Him alone.
** Allah do not depends on anything He has created; on the contrary, everything else depends on Him.
** All the prophets were humans like us with the exception that they were chosen by Allah for giving good news to their fellow people and warning them with the revelations made to them through Gabrael (pbuh).
** The job of prophethood ended with their death.

Say you have a case with the highest court of the country in some matter and there is a specific enactment about it in your favour in one of so many enactments. But unfortunately your lawers have no knowledge of the concerned enactment. Nor are the judges aware of the law. In this case, the lawers will argue from the point of ordinary justice, equity and fairness etc. and the judges are likely to pass an order quite diffrerent from that of the relevant law, themselves making a different law(judge-made law) on a matter in which an Act of the Parliament is already in existence. The case here is adjudged other than by the Act of Parliament for ignorance.

But it is never acceptable in case of a scholar in matters of the religion that he will be very versed in hadith and fiqhs, but not so in the Quran, should be followed. Nor is it advisable that she should innovate any knowlede which is not connected with the "obey Allah and obey the prophet'' ordainment.