Those who believed and whose hearts are tranquil with the remembrance of Lord Allah. Know that, with the remembrance of Allah, hearts will achieve tranquility.
The remembrance of Lord can be formed only by transforming one's Jinn soulmate into a believer with Adhikr as explained in verse 2: 152. At the time of believer's death, Lord will tell him: "Oh the one whose soul has become tranquil with Adhikr, you return into your Lord by pleasing Him and pleased by Him; so you enter in My Service, you enter in My Paradise", as told in verses 89: 27-30.
By rejecting Adhikr, the Arabic Quran reading Fujjar are serving Satan as explained in verse 7: 26. They are deaf and dumb towards Adhikr without utilizing their intelligence. Thus, they became the worst among the 1000 communities of Lord's creatures as explained in verses 8: 22 and 55. Verses 87: 9-13 say: “Dhikra (Reminder) may be useful to those who fear Lord. Certainly, you will remind the fearful one, indeed, the unluckiest will abstain It, the one who will be roasted in the great Fire; then he will not die and live in it”. See explanation 3: 90-91; 8: 2-4 and 48.