Muhammad bin Qais, may Allah have mercy on him, regarding the statement of Allah the Exalted: ﴿إِنَّمَاحَرَّمَرَبِّيَالْفَوَاحِشَمَاظَهَرَمِنْهَاوَمَابَطَنَ﴾ said: «مَاظَهَرَ» That is, the apparent indecency refers to the fact that they used to circumambulate the House of Allah naked, and «مَابَطَنَ» that is, the hidden indecency refers to adultery.
Hadith Referenceسنن سعید بن منصور / كتاب التفسير / 934