It is narrated from Sayyidina Umar (Allah be pleased with him) that Prophet of Allah (blessings and peace of Allah be upon him) said,
‘The worst thing I fear for my Ummah are the hypocrites who are knowledgeable speakers.’
Allama Munawi (Allah have mercy on him) said, this is the person who is expert in knowledge and can easily speak at lengths but by his heart (qalb) and actions he is an ignorant with corrupt beliefs. However, with his cunning speech he can misguide the public.
Taharat al-Quloob, page 42-3
This is an eye opener for all of us.
[Hypocrisy: a pretense of having a virtuous character, moral or religious beliefs or principles, etc., that one does not really possess.]
We need to check ourselves first, whether we are in this category.
Also, it gives as the clear direction that we should not be misled by speeches alone. The most important thing to see is the action of the speaker.
Is it in conformity with the teachings of Quran and Sunna, as done by our pious predecessors?
If not then it must be clear that ostentatious traditional garb (beards, turban, jubba, tasbih, etc.) or verbose heartrending stories or superb vernacular or expertise in contemporary marketing techniques (like stylish and sleek power point presentations, projectors, top of the line sound system, online state of the art setup, etc.) will not be spiritually beneficial at all.
Moreover, there is a greater chance that the speaker’s hypocrisy will be transferred to us.
A considerable research, companionship and sincere advice from pious knowledgeable individuals is required to ascertain the sincerity of a speaker to benefit from him spiritually.
wa tawfiqi ila billah!