Sister Sobia
Instead of emotional arguments it would be nice if you could explain how the critics of this person or that person or any person are right or wrong.
Only then will we come to an objective conclusion.
Just saying "defamation" or "they're criticizing him" are emotional arguments.
Defamation can be valid and can be invalid too. If someone says something about khomeini, will you still say "scholars are being defamed"?
No sister, we need to see what is being said AND what are the evidences for it. That's all.
If you feel nazim al-qubrusi does not violate the shari'a in the video shown, please bring forward your evidence for it from the shari'a or make the case that the video is doctored.
Otherwise, presenting emotional arguments is only an indication of a guilty conscience that you indeed believe the person to be in the wrong and is only hurtful to the case you are trying to make.
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You are very wrong to say that you accepted Islam through his guidance sister.
Guidance ONLY comes from Allah.
He could only have given you some material knowledge and that won't undo any wrong teachings or actions that he may have. The two (any material knowledge he provided you and any wrong beliefs/actions on his part) are mutually exclusive.
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I'm sorry to say sister, but you are again very wrong in assuming the subcontinental people consider themselves bastions of Islam or the Ahlus Sunnah.
I have lived a few years in this person's native country and fluently speak his native language of Turkish and know for a fact that he is not appreciated in many Sunni Naqshbandi circles amongst his own Turkish peoples and also many Bosnians.
In fact he is lesser known in Turkey than he is in the west. He is popular in Turkish Cyprus because that's his native island with a population of roughly 270,000 ONLY.
He is not known in mainland Turkey the way he is known in the west. Its a safe bet to say roughly 60% of Istanbul (as a bare minimum) wouldn't have even heard of him.
On the contrary he is extremely popular in European Sunni/Sufi circles. Propaganda and media hype can and do work wonders.
There are plenty of Arab, Turkish, North & sub-Saharan African, Indonesian, Malay, Bosnian etc. scholars who have nothing to do with the subcontinent whom we exonerate as the torchbearers of the Ahlus Sunnah, both on forums as well as real life.
The problem with those of us living in the west is that 1) we are minorities to start with and 2) everything is dependent on media-based popularity and there are only a few countable people (regardless whether you consider them right or wrong) who are popular and well known. Try to list out to yourself the number of Sunni scholarly personalities that you know. I'd be very shocked if you can come up with more than 20-30 tops!
That's not even a start in each of the places like Yemen, Syria, Jordan, Palestine, Turkey (DESPITE all its modernism), Pakistan, India, Indonesia, Malaysia, Central Asia.... the list goes on - with plenty of them silently doing work for the deen, who are not even famous. Its always refreshing and pleasantly surprising and an iman booster to learn of a sheikh one didn't know of who has dedicated so beautifully to the deen and is also on the correct methodology of the Ahlus Sunnah - in Morocco, in Yemen, in Turkey, etc.
As much as us western-based Muslims (regardless if we are Subcontinentals or Arabs or Turks or anything) might see various issues with life "back home" or some of the attitudes towards religion and the intertwining of culture and religion, etc - one thing is certain - there are still PLENTY of shuyukh who are of a far far far superior academic caliber than those popularly known in the west.
Sure, the amount of hucksters we have "back home" are also beyond plentiful. I guess it's just directly proportional to the populations.
I hope insha Allah you will look at my post objectively rather than emotionally.
My aim is not to get you to dislike a person you might consider a rightly guided sheikh. My only hope is that you can see things objectively for yourself and also convey them to others objectively.