Al-Kalbi said: They said, 'Bring us a sign so we know that Allah has chosen him over us.' 'And their prophet said to them, "Indeed, the sign"'—meaning, the evidence—'"of his dominion is that there will come to you the Ark, in which is tranquility from your Lord."' Yahya said: Meaning, mercy from your Lord, according to the interpretation of some of them.

Muhammad said: It is said: 'Tranquility' (Sakinah) is in the form of the noun pattern 'fa'ilah' from 'al-sukoon' (stillness/calm); the meaning is: in it is that which will bring you tranquility when it comes to you.