52:12
ٱلَّذِينَ هُمْ فِى خَوْضٍۢ يَلْعَبُونَ ١٢
Saheeh International
Who are in [empty] discourse amusing themselves.
Tafsir of "Ibn Kathir" (English)
Those who were in their falsehood, playing.meaning, they live in this life in falsehood and make the religion the subject of their mockery and jest