And those to whom We had given the Book rejoice with what has been revealed to you, but among them, there are groups those who deny some parts of It. You say: "I have only been commanded to serve Lord Allah and not to associate anything with Him. I call you into Him, and unto Him is my return".
All Messengers are sent with Adhikr-the Truth and Proof-as told in verse 21: 24. When the last version of Adhikr is sent down to Messenger Muhammad, a few who have believed with the Book before rejoiced with It testifying verses 10: 57-59. But 999 out of each 1000 disintegrated into different groups by rejecting Adhikr-the Straightpath-as explained in verse 4: 118. Today, Adhikr-the Three-Time-Knowledge-is codified as a Book. So, whoever from Arabic Quran reading Fujjar is hiding and rejecting It, then the Fire is promised to them as explained in verse 11: 17. The evil commanding hypocrites and Kuffar are promised with Hellfire as explained in verses 9: 67-68.
The believer who testifies Adhikr is calling mankind into the Lord of the Universe. He will only have the consciousness that all of us belong to Lord and into Him is our return as explained in verses 2: 156-157. See explanation 2: 121; 3: 199; 10: 104-106 and 11: 62.