Surah Al-Isra, ayah 32

وَلَا تَقۡرَبُواْ ٱلزِّنَىٰٓۖ إِنَّهُۥ كَانَ فَٰحِشَةٗ وَسَآءَ سَبِيلٗا ٣٢

Walā taqrabuz-zinā innahū kāna fāhishatan wasā'a sabīlā

And do not approach unlawful sexual intercourse.⁷⁴¹ Indeed, it is ever an immorality and is evil as a way.