The Jinns stealing Information from the Sky before the the Messenger ﷺ was sent and striking Them with flaming Fire after His Coming.

Allah informs about the Jinns when He sent His Messenger Muhammad ﷺ and revealed the Qur'an to him. Among the ways He protected it (the Qur'an) was by filling sky with stern guards guarding it from all of its sides. The devils were then expelled from the places where they used to sit prior to that. This was so that they could not steal anything from the Qur'an and tell it to the soothsayers, thereby causing matters to be confused and mixed up. If this happened it would not be known who was being truthful. Allah did this out of His kindness to His creation, His mercy upon His servants and His protection of His Mighty Book (the Qur'an). This is why the Jinns said,

وَأَنَّا لَمَسْنَا السَّمَآءَ فَوَجَدْنَـهَا مُلِئَتْ حَرَساً شَدِيداً وَشُهُباً - وَأَنَّا كُنَّا نَقْعُدُ مِنْهَا مَقَـعِدَ لِلسَّمْعِ فَمَن يَسْتَمِعِ الاٌّنَ يَجِدْ لَهُ شِهَاباً رَّصَداً

وَأَنَّا لَا نَدْرِ‌ي أَشَرٌّ‌ أُرِ‌يدَ بِمَن فِي الْأَرْ‌ضِ أَمْ أَرَ‌ادَ بِهِمْ رَ‌بُّهُمْ رَ‌شَدًا (and that we do not know whether it is a bad end that is intended for those on earth, or their Lord has intended for them a right thing,....72:10). The Jinn and devils were barred from having access to heavenly news. In this case it would be a punishment for the inhabitants of the earth. However, if Allah intends them to be rightly guided, He has barred the Jinn and Shaitan from having access to the heaven, so that they do not interfere with Divine revelation. Therefore, they expressed their reservations about this to the effect that they had no idea as to whether it was a bad end that was intended for the inhabitants of the earth or whether Allah intended them to be rightly guided.