Word by Word Analysis

إِنَّ ٱلَّذِينَ يُحِبُّونَ أَن تَشِيعَ ٱلْفَـٰحِشَةُ فِى ٱلَّذِينَ ءَامَنُوا۟ لَهُمْ عَذَابٌ أَلِيمٌ فِى ٱلدُّنْيَا وَٱلْـَٔاخِرَةِ ۚ وَٱللَّهُ يَعْلَمُ وَأَنتُمْ لَا تَعْلَمُونَ 19

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 Allāh knows and you do not know.