إِنَّ شَرَّ ٱلدَّوَآبِّ عِندَ ٱللَّهِ ٱلَّذِينَ كَفَرُواْ فَهُمۡ لَا يُؤۡمِنُونَ ٥٥
Indeed, the worst of living creatures in the sight of Allāh are those who have disbelieved, and they will not [ever] believe-
Translation: Saheeh International (English)
Each word's meaning and sound
The worst of those who walk on the earth are those who disbelieve in Allah and His messengers, and who would not believe even if every sign was to come to them – they would still persist in disbelief. The means of guidance – such as intellect, hearing and sight – are of no use to these people.
Al-Mukhtasar in interpreting the Noble Quran