Examine carefully the speech of everyone you hear from (particularly) in your time particularly

Imaam Abu Muhammadal Barbahaaree (d. 329 H رحمه الله), said in 
his Sharh Us-Sunnah:

May Allaah have mercy upon you! Examine carefully the speech of everyone you hear from in your time particularly. So do not act in haste and do not enter in anything from it until you ask and see: Did any of the Companions of the Prophet, may Allaah’s praise and salutations be upon him, speak about it, or did any of the scholars? So if you find a narration from them about it, cling to it, do not go beyond it for anything and do not give precedence to anything over it and thus fall into the Fire.

In Explanation to the above Sheikh Saaleh al-Fawzaan (حفظه الله) mentioned :

Do not be hasty in accepting as correct what you may hear from the people especially in these later times. As now there are many who speak about so many various matters, issue rulings and ascribing to themselves both knowledge and the right to speak. This is especially the case after the emergence and spread of new modern day media technologies. Such that everyone now can speak and bring forth that which is in truth worthless; by this meaning words of no true value – speaking about whatever they wish in the name of knowledge and in the name of the religion of Islaam.

It has even reached the point that you find the people of misguidance and the members of the various groups of misguidance and deviance from the religion speaking as well. Such individuals have now become those who speak in the name of the religion of Islaam through means such as the various satellite television channels. Therefore be very cautious!

It is upon you O Muslim, and upon you O student of knowledge individually, to verify matters and not rush to embrace everything and anything you hear.

It is upon you to verify the truth of what you hear, asking, ‘Who else makes this same statement or claim?’, ‘Where did this thought or concept originate or come from?’, ‘Who is its reference or source authority?’

Asking what are the evidences which support it from within the Book and the Sunnah? And inquiring where has the individual who is putting this forth studied and taken his knowledge from? From who has he studied the knowledge of Islaam?

Each of these matters requires verification through inquiry and investigation, especially in the present age and time. As it is not every speaker who should rightly be considered a source of knowledge, even if he is well-spoken and eloquent, and can manipulate words captivating his listeners.

Do not be taken in and accept him until you are aware of the degree and scope of what he possesses of knowledge and understanding. As perhaps someone’s words may be few, but possesses true understanding, and perhaps another will have a great deal of speech yet he is actually ignorant to such a degree that he doesn’t actually possess anything of true understanding. Rather he only has the ability to enchant with his speech so that the people are deceived. Yet he puts forth the perception that he is a scholar, that he is someone of true understanding and comprehension, that he is a capable thinker, and so forth. Through such means and ways, he is able to deceive and beguile the people, taking them away from the way of truth. Therefore what is to be given true consideration is not the amount of the speech put forth or that one can extensively discuss a subject. Rather the criterion that is to be given consideration is what that speech contains within it of sound authentic knowledge, what it contains of the established and transmitted principles of Islaam.

As perhaps a short or brief statement which is connected to or has a foundation in the established principles can be of greater benefit than a great deal of speech which simply rambles on, and through hearing you can’t actually receive very much benefit from.

This is the reality which is present in our time; one sees a tremendous amount of speech which only possesses within it a small amount of actual knowledge. We see the presence of many speakers yet few people of true understanding and comprehension.’

Transcribed from : ‘A Valued Gift for the Reader of Comments Upon the Book Sharh Us-Sunnah‘, pages 102-103 | Sheikh Saaleh Ibn Fawzaan al-Fawzaan (حفظه الله)