Surah An-Nur 24:2

ٱلزَّانِيَةُ وَٱلزَّانِى فَٱجْلِدُوا۟ كُلَّ وَٰحِدٍ مِّنْهُمَا مِا۟ئَةَ جَلْدَةٍ ۖ وَلَا تَأْخُذْكُم بِهِمَا رَأْفَةٌ فِى دِينِ ٱللَّهِ إِن كُنتُمْ تُؤْمِنُونَ بِٱللَّهِ وَٱلْيَوْمِ ٱلْـَٔاخِرِ ۖ وَلْيَشْهَدْ عَذَابَهُمَا طَآئِفَةٌ مِّنَ ٱلْمُؤْمِنِينَ

The [unmarried] woman or [unmarried] man found guilty of sexual intercourse - lash each one of them with a hundred lashes, and do not be taken by pity for them in the religion [i.e., law] of Allāh, if you should believe in Allāh and the Last Day. And let a group of the believers witness their punishment.

Translation: Saheeh International

Tafsir

As for the fornicatress and the fornicator that is of those not in wedlock — because those in wedlock are stoned according to the Sunna the al in al-zāniya ‘the fornicatress’ and al-zānī ‘the fornicator’ according to some mentioned opinions is a relative particle; …

Excerpt from Tafsir al-Jalalayn, commentary on 24:2, via Quran.com. The reader has the full commentary and 9 more tafsirs.