Surah 97. Al-Qadr, Ayah 5

Lit., "it is salvation (salam, see surah {5}, note [29]) - i.e., it makes the believer secure from all spiritual evil: thus Mujahid (as quoted by Ibn Kathir), evidently implying that a conscious realization of the sanctity of this night acts as a shield against unworthy thoughts and inclinations.

When the Night of spiritual darkness is dissipated by the glory of Allah, a wonderful Peace and a sense of Security arise in the soul. And this lasts on until this life closes, and the glorious Day of the new world dawns, when everything will be on a different plane, and the chequered nights and days of this world will be even less than a dream.