﴿ إِلَٰهُكُمْ إِلَٰهٌۭ وَٰحِدٌۭ ۚ فَٱلَّذِينَ لَا يُؤْمِنُونَ بِٱلْءَاخِرَةِ قُلُوبُهُم مُّنكِرَةٌۭ وَهُم مُّسْتَكْبِرُونَ ﴾

“Your God is the One God: but because of their false pride, the hearts of those who do not believe in the life to come refuse to admit this [truth].”

(Your God is One God) He knows this, not your idols. (But as for those who believe not in the Hereafter) those who do not believe in resurrection after death (their hearts refuse to know) acknowledge Allah's divine Oneness, (for they are proud) too proud to believe.