Surah Ghafir — Ayah 84 (40:84)
فَلَمَّا رَأَوۡاْ بَأۡسَنَا قَالُوٓاْ ءَامَنَّا بِٱللَّهِ وَحۡدَهُۥ وَكَفَرۡنَا بِمَا كُنَّا بِهِۦ مُشۡرِكِينَ ٨٤
English translation (Saheeh International)
And when they saw Our punishment, they said, "We believe in Allāh alone and disbelieve in that which we used to associate with Him."
Brief commentary
Then, when they saw My punishment they began confessing, at a time when no confession would benefit them, saying, “We bring faith upon Allah alone, and reject whatever partners and idols we would worship instead of Him.”