The Quran

۞ هٰذانِ خَصمانِ اختَصَموا في رَبِّهِم ۖ فَالَّذينَ كَفَروا قُطِّعَت لَهُم ثِيابٌ مِن نارٍ يُصَبُّ مِن فَوقِ رُءوسِهِمُ الحَميمُ

Muhammad Asad

These two contrary kinds of man¹ have become engrossed in contention about their Sustainer. But [thus it is:] as for those who are bent on denying the truth² - garments of fire shall be cut out for them [in the life to come]; burning despair³ will be poured over their heads,

Lit., "these two adversaries" or "antagonists", i.e., those who believe in God's oneness and uniqueness, and those who ascribe divine qualities to beings other than Him, or even deny His existence altogether.
I.e., in distinction from those who err out of ignorance.
For this rendering of hamim, see note 62 on the concluding sentence of 6:70, as well as note 65 on 14:50 and note 7 on 73:12-13, which mention Razi's interpretations of similar allegorical descriptions of the suffering that will befall the sinners in the hereafter.