Surah Al-Mu'minun 23:66

قَدْ كَانَتْ ءَايَـٰتِى تُتْلَىٰ عَلَيْكُمْ فَكُنتُمْ عَلَىٰٓ أَعْقَـٰبِكُمْ تَنكِصُونَ

My verses had already been recited to you, but you were turning back on your heels.

Translation: Saheeh International

Tafsir

Verily My signs in the Qur’ān used to be recited to you but you used to take to your heels falling back in retreat

Excerpt from Tafsir al-Jalalayn, commentary on 23:66, via Quran.com. The reader has the full commentary and 9 more tafsirs.