Speaking in the Affairs of Deen and 'Ilm Without Knowledge- Shaykh Salih al-Fawzaan
ash-Shaykh, al-'Allaamah Saalih al-Fawzaan mentions in his explanation of Sharhus-Sunnah of al-Imaam al-Hassan bin 'Alee al-Barbahaaree (رحمه الله) [pp.266-267]:
"And if a person speaks about something he is not specialized and competent in, the affairs are corrupted. So it is a must that no one speaks in the affairs of the Deen and 'Ilm except the people who are specialized and the People of Knowledge. So it is not correct that the affair be chaos and disorder - every one speaking and claiming to have knowledge - like is present now, from the students who become bold enough (to enter into) the matters of 'Aqeedah and speak regarding them, so they speak about Eemaan and the reality of Eemaan, and they speak in things and they are people who are insignificant and don't carry any weight; they have no knowledge, and they haven't studied with the 'Ulamaa', rather they have only studied on their own, and they rely upon their own understanding, and they have reached a point where they lay down principles from themselves and from their own understanding, so the affair is extremely dangerous."
Speaking in the affairs of deen and 'Ilm without knowledge- Shaykh Salih al-Fawzaan