Surah 48:4
"He (it is) who sent down the Sakīna into the hearts of the believers, so that they might add belief to their belief – to God (belong) the forces of the heavens and the earth, and God is knowing, wise –"
48.4 – He (it is) who sent down the Sakīna into the hearts of the believers
The Arabic word Sakīna appears three times in this sūra: Allah sends down Sakīna on his messenger (v. 26) and on the “believers” (vv. 4, 18, 26). See the comment on Sakīna at 2.248.
- from The Quran with Christian Commentary: A Guide to Understanding the Scripture of Islam