Bangladeshi police arrested  Shariat Sarkar (40), a famous Baul  (Sufi folk) artist, for allegedly making comments that hurt the “religious sentiment” of Muslims. He was charged with violating Section 28  of the draconian  Digital Security Act.
During a concert in late December 2019, he allegedly criticized  religious Muslim clerics who oppose singing and had offered a 5 million taka (58,800 USD) challenge to anyone who can prove that music is forbidden under Islamic scripture.
Baul Shariat Sarkar arrested under digital security act-454009 https://t.co/mD0uZQHdj6 
— Daily-Sun (@dailysunbd) January 13, 2020 
A video of his performance was posted on YouTube (which was later removed) and went viral on social media. Others, however, continued to upload the video .
Some conservatives led by Muslim clerics took to the streets in different places protesting  against his alleged derogatory comments about Islam, the Quran and the Muslim clerics. An individual from his locality in Tangail district (100km from capital Dhaka) sued him on January 9 for allegedly hurting religious sentiments which led to his arrest .
The court has sent him to judicial custody  on completion of his three-day interrogation in police custody. As of this writing, his bail has not been set.
Is music forbidden in Islam?
The question of whether music is allowed in Islam  is historically disputed and the practice varies in regions. Famous Muslim scholar Imam al-Ghazzali , commented centuries ago citing scriptures that music is permitted . However, some Salafists  and Wahhabi groups  of Muslims interpret some verses in the Quran as evidence that music is haram  (forbidden).
Who are the Bauls?
Bauls  are a group of mystic minstrels from Bangladesh who have a strong musical tradition. They are a very heterogeneous group, with many sects. However, most of them belong to the Vaishnava Hindu and Sufi Muslim religions. Baul music is a particular type of folk song, which can be philosophic and devotional and often celebrate divine love.
The songs that the Baul Shariat Sarker sings are embedded in the Sufi genre. The history of Sufism  in Bangladesh is ancient. Islam spread in Bangladesh mainly through the work of Sufis.
Widespread protests against his detention
Progressives and cultural activists in the country have reacted angrily to the arrest of the Baul artist under the Digital Security Act. Human chains and protest rallies  were organized by various artist organizations demanding his release.
Writer Swakrito Noman highlighted the spirituality of Islam and mentioned that  the arrest of Shariat Sarkar was wrong:
শরিয়ত বয়াতির পুরো ভিডিও ক্লিপটি শুনেছি। তিনি কোথাও ধর্মের বিরুদ্ধে কিছু বলেননি। তিনি কোথাও আপত্তিকর কিছু বলেননি। তিনি ধর্মের নামে ভণ্ডামির বিরুদ্ধে বলেছেন, ধর্মব্যবসার বিরুদ্ধে বলেছেন। তার কথা বুঝতে হলে আগে বুঝতে হবে ইসলামের অধ্যাত্মিক দিকটিকে। শাস্ত্রের পাশাপাশি ইসলামে অধ্যাত্মও স্বীকৃত। বুঝতে হবে বহুধা বিভক্ত ইসলামকে। শরিয়ত বয়াতিরা ইসলামের অধ্যাত্ম ধারার অনুসারী। তাকে শাস্ত্র দিয়ে বিচার করাটা মূর্খতা। রক্ষণশীল মোল্লা-মৌলবিদের কথায় তাকে গ্রেপ্তার করাটা অন্যায়।
I have listened to the entire video clip of Shariat Bayati (singer). He did not say anything derogatory or anything offensive against religion. He talked about hypocrisy in the name of religion, against fraudulent religious practices. To understand his words, one must first understand the spiritual side of Islam and the many divided sects of Islam. Bauls like Shariat follow the spiritual interpretation of Islam (Sufism). It is foolish to judge him by the words of Scriptures. It is unfair to arrest him listening to the allegations of the conservative Muslim clerics.
Journalist Kabir Ahmed thinks  that his arrest was not appropriate even if music is forbidden in Islam since Bangladesh is supposedly a democracy:
‘কেতাবে’ যদি গান-বাজনা ‘হারাম’ লেখা থাকে তবে কি শরিয়ত সরকার বাউলের গ্রেপ্তার জায়েজ হয়ে যাবে? আমার উত্তর- ‘না’!
আপনি যে কেতাবকে উদ্দিষ্ট ভাবছেন সেটা আপনার-আমার ব্যক্তিগত বিশ্বাসের, স্রেফ ব্যক্তিগত; রাষ্ট্রীয় নয়।… https://t.co/8gBHJO20iF 
— কবির য়াহমদ (@kabiraahmed) January 13, 2020 
Can the arrest of Baul Shariat Sarker be justified if it was specified in the Quran as ‘haram’ (forbidden)? My answer is – no! How you are perceiving the holy book is your personal belief, just personal; it's not a nationwide issue.
Journalist and author Raju Alauddin  wants to know on which basis or criteria the conservatives deemed that his statement is offensive:
শরিয়ত বয়াতির কথাটা কী কারণে আপত্তিকর, সেটা কোন মানদণ্ডের ভিত্তিতে আপত্তিকর বা কুরুচিপূর্ণ তার কোনোই ব্যাখ্যা নেই। কিন্তু তাকে রিমান্ডে নেয়া হয়েছে, এখন হাজতে তিনি। হায়, অন্ধকারে নিমজ্জিত আমার স্বদেশ!
I saw no clear explanation of why Shariat Bayati's words were deemed offensive; malicious on which standards? Nevertheless, he was arrested and he landed in jail. Alas, my country is immersed in darkness!
Journalist and development activist Shariful Hassan urged the country's scholars to take on Shariat Sarker's challenge instead of suing or harming him:
বয়াতি শরিয়ত সরকার উন্মুক্ত চ্যালেঞ্জ জানিয়েছিলেন–কেউ যদি কোরআনের রেফারেন্স দিয়ে প্রমান করতে পারে, গান-বাজনা হারাম; তিনি তাকে ৫০ লক্ষ টাকা দেবেন। মামলা বা গ্রেপ্তার না করে চ্যালেঞ্জটা নেন কোন আলেম ভাই। https://t.co/V9xbNLcEt3 
— Shariful Hasan (@hasan06du) January 12, 2020 
Shariat Sarker openly challenged – if anyone can provide a reference in the Qur'an, that music is forbidden; he will pay that person 5 million BDT (USD 58,800). Without suing him or asking for his detention, any Islamic scholar could take the challenge and earn that money (if he is wrong).
A challenge to the Sufi tradition in Bangladesh
The liberal policies of Sufism have a significant impact on the people of Bangladesh who learned to mix culture with religion. However, in recent decades, a hostile environment against the Sufis emerged due to threats  from conservatives who think Sufis are “deviants from mainstream Islam”. Simon Zakaria, a folk music researcher at the Bangla Academy, told BBC Bangla :
বাংলাদেশ স্বাধীন হবার পরে একটি ধর্মীয় গোষ্ঠী ব্যাপক ভাবে পৃষ্ঠপোষকতা পেয়েছে, আমাদের সাংস্কৃতিক মনস্তত্ব পরিবর্তিত হয়ে গেছে, আমাদের শিক্ষায় ও প্রশাসনে এসব বিষয় প্রাধান্য পাচ্ছে।
After the liberation of Bangladesh, a specific religious group (conservatives) has been widely patronized and our cultural mindset has changed gradually. These influences are gaining prominence in our education and administration.
Controversial digital security law
The Digital Security Act 2018 criminalizes various types of online speech, ranging from defamatory messages to statements that “injures religious values or sentiments.” Section 28 of the act  says:
“If any person or group intentionally or knowingly with the aim of hurting religious sentiments or values or with the intention to provoke publish or broadcast anything by means of any website or any electronic format which hurts religious sentiment or values, then such activity of that person will be considered an offence.”
Journalists and rights activists expressed concerns about the act from the beginning, and many lawsuits were lodged  against writers, poets and activists using this act. In addition to condemning the detention of Shariat Sarker, many have demanded the repeal of the controversial law.
Human Rights Forum Bangladesh, a newly formed group for activists, expressed  grave concern on the arrest of Shariat Sarker and demanded his immediate release.
If convicted, Sarker can be imprisoned from 3 to 7 years according to the Digital Security act .