The Light
إِنَّ ٱلَّذِينَ يُحِبُّونَ أَن تَشِيعَ ٱلْفَـٰحِشَةُ فِى ٱلَّذِينَ ءَامَنُوا۟ لَهُمْ عَذَابٌ أَلِيمٌ فِى ٱلدُّنْيَا وَٱلْـَٔاخِرَةِ ۚ وَٱللَّهُ يَعْلَمُ وَأَنتُمْ لَا تَعْلَمُونَ
Indeed, those who like that immorality should be spread [or publicized] among those who have believed will have a painful punishment in this world and the Hereafter. And Allah knows and you do not know.
Nearby ayahs help place verse 24:19 in sequence and meaning.
يَعِظُكُمُ ٱللَّهُ أَن تَعُودُوا۟ لِمِثْلِهِۦٓ أَبَدًا إِن كُنتُم مُّؤْمِنِينَ
Allah warns you against returning to the likes of this [conduct], ever, if you should be believers.
وَيُبَيِّنُ ٱللَّهُ لَكُمُ ٱلْـَٔايَـٰتِ ۚ وَٱللَّهُ عَلِيمٌ حَكِيمٌ
And Allah makes clear to you the verses, and Allah is Knowing and Wise.
وَلَوْلَا فَضْلُ ٱللَّهِ عَلَيْكُمْ وَرَحْمَتُهُۥ وَأَنَّ ٱللَّهَ رَءُوفٌ رَّحِيمٌ
And if it had not been for the favor of Allah upon you and His mercy... and because Allah is Kind and Merciful.
۞ يَـٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُوا۟ لَا تَتَّبِعُوا۟ خُطُوَٰتِ ٱلشَّيْطَـٰنِ ۚ وَمَن يَتَّبِعْ خُطُوَٰتِ ٱلشَّيْطَـٰنِ فَإِنَّهُۥ يَأْمُرُ بِٱلْفَحْشَآءِ وَٱلْمُنكَرِ ۚ وَلَوْلَا فَضْلُ ٱللَّهِ عَلَيْكُمْ وَرَحْمَتُهُۥ مَا زَكَىٰ مِنكُم مِّنْ أَحَدٍ أَبَدًا وَلَـٰكِنَّ ٱللَّهَ يُزَكِّى مَن يَشَآءُ ۗ وَٱللَّهُ سَمِيعٌ عَلِيمٌ
O you who have believed, do not follow the footsteps of Satan. And whoever follows the footsteps of Satan - indeed, he enjoins immorality and wrongdoing. And if not for the favor of Allah upon you and His mercy, not one of you would have been pure, ever, but Allah purifies whom He wills, and Allah is Hearing and Knowing.