يُثَبِّتُ اللَّهُ الَّذِينَ آمَنُوا بِالْقَوْلِ الثَّابِتِ
Allah makes the believers firm with the firm word. (Qurʾan 14:27)
This verse is linked, through reports concerning grave questioning, to the believer being made steadfast. Tathbīt signifies being established upon the truth by Allah's enabling grace.
The wording of the verse is broad; its more specific application to questioning in the grave is conveyed through the relevant reports. A sound explanation distinguishes the verse's general meaning from a particular application established by Hadith.