At-Taubah - 9:115

وَمَا كَانَ اللّهُ لِيُضِلَّ قَوْمًا بَعْدَ إِذْ هَدَاهُمْ حَتَّى يُبَيِّنَ لَهُم مَّا يَتَّقُونَ إِنَّ اللّهَ بِكُلِّ شَيْءٍ عَلِيمٌ
[9:115]
It is not (attributable to) Allah that He should lead a people astray after He has guided them; He even makes clear to them what they should guard against; surely Allah knows all things.
And Allah will not mislead a people after He hath guided them, in order that He may make clear to them what to fear (and avoid)- for Allah hath knowledge of all things.
It was never Allah's (part) that He should send a folk astray after He had guided them until He had made clear unto them what they should avoid. Lo! Allah is Aware of all things.