Translation of the verse 28 from Surah Ar-Ra‘d : Number of verses 43 - - page 252 - Part 13.
Those who believe (in the Oneness of Allah - Islamic Monotheism), and whose hearts find rest in the remembrance of Allah, Verily, in the remembrance of Allah do hearts find rest.
Those who have believed and whose hearts are assured by the remembrance of Allah. Unquestionably, by the remembrance of Allah hearts are assured."
(13:28) Such are the people who have accepted (the Message of this Prophet,) and their hearts find comfort in the remembrance of Allah. Note it well that it is Allah's remembrance alone that brings comfort to hearts.