Surah Al-Ma'idah 5:58

وَإِذَا نَادَيْتُمْ إِلَى ٱلصَّلَوٰةِ ٱتَّخَذُوهَا هُزُوًا وَلَعِبًا ۚ ذَٰلِكَ بِأَنَّهُمْ قَوْمٌ لَّا يَعْقِلُونَ

And when you call to prayer, they take it in ridicule and amusement. That is because they are a people who do not use reason.

Translation: Saheeh International

Tafsir

And those who when you make the call to prayer take it that is the prayer in mockery and as a game mocking it and laughing at it among themselves; that mocking attitude is because they are a people who do not understand.

Excerpt from Tafsir al-Jalalayn, commentary on 5:58, via Quran.com. The reader has the full commentary and 9 more tafsirs.