Qatadah (may Allah have mercy on him) said: Regarding this verse: «﴿فَأَمَّاالَّذِيْنَآمَنُوْافَيَعْلَمُوْنَأَنَّهُالْحَقُّمِنْرَبِّهِمْ . . . . . .﴾»[البقره: 26/2], it means that the believers know that this is the speech of the Most Merciful.
Hadith Referenceسنن دارمي / من كتاب فضائل القرآن / 3384