Shaykh Yasir Qadhi makes us comprehend aptly about chapters 48 and 49 of the book Kitaab At Tawheed.
Chapter 48 talks about those who make fun of anything where mention is made of Allah or the Qur'an or the Messenger ﷺ and they are the ones who have committed Kufr or disbelief.
We are made aware of how there is a difference between backbiting and admonition, and loyalty to Allah and His Messenger ﷺ and also an understanding of the difference between forgiveness which Allah loves and severity in dealing with the enemies of Allah.
Chapter 49 deals with the issue of how it is to say - "This wealth is the result of my labour and knowledge" and how this is against Tawhid. Verses of the Qur'an are sought to seek clarifications about this grave error we do.