46:12
وَمِن قَبْلِهِۦ كِتَـٰبُ مُوسَىٰٓ إِمَامًا وَرَحْمَةً ۚ وَهَـٰذَا كِتَـٰبٌ مُّصَدِّقٌ لِّسَانًا عَرَبِيًّا لِّيُنذِرَ ٱلَّذِينَ ظَلَمُوا۟ وَبُشْرَىٰ لِلْمُحْسِنِينَ
And before it was the scripture of Moses to lead and as a mercy. And this is a confirming Book in an Arabic tongue to warn those who have wronged and as good tidings to the doers of good.
Context in Surah Al-Ahqaf
Nearby ayahs help place verse 46:12 in sequence and meaning.
قُلْ أَرَءَيْتُمْ إِن كَانَ مِنْ عِندِ ٱللَّهِ وَكَفَرْتُم بِهِۦ وَشَهِدَ شَاهِدٌ مِّنۢ بَنِىٓ إِسْرَٰٓءِيلَ عَلَىٰ مِثْلِهِۦ فَـَٔامَنَ وَٱسْتَكْبَرْتُمْ ۖ إِنَّ ٱللَّهَ لَا يَهْدِى ٱلْقَوْمَ ٱلظَّـٰلِمِينَ
Say, "Have you considered: if the Qur'an was from Allah, and you disbelieved in it while a witness from the Children of Israel has testified to something similar and believed while you were arrogant...?" Indeed, Allah does not guide the wrongdoing people.
وَقَالَ ٱلَّذِينَ كَفَرُوا۟ لِلَّذِينَ ءَامَنُوا۟ لَوْ كَانَ خَيْرًا مَّا سَبَقُونَآ إِلَيْهِ ۚ وَإِذْ لَمْ يَهْتَدُوا۟ بِهِۦ فَسَيَقُولُونَ هَـٰذَآ إِفْكٌ قَدِيمٌ
And those who disbelieve say of those who believe, "If it had [truly] been good, they would not have preceded us to it." And when they are not guided by it, they will say, "This is an ancient falsehood."
إِنَّ ٱلَّذِينَ قَالُوا۟ رَبُّنَا ٱللَّهُ ثُمَّ ٱسْتَقَـٰمُوا۟ فَلَا خَوْفٌ عَلَيْهِمْ وَلَا هُمْ يَحْزَنُونَ
Indeed, those who have said, "Our Lord is Allah," and then remained on a right course - there will be no fear concerning them, nor will they grieve.
أُو۟لَـٰٓئِكَ أَصْحَـٰبُ ٱلْجَنَّةِ خَـٰلِدِينَ فِيهَا جَزَآءًۢ بِمَا كَانُوا۟ يَعْمَلُونَ
Those are the companions of Paradise, abiding eternally therein as reward for what they used to do.