Is it permissible to speak of worldly matters while remembering God?

The remembrance of Allah (dhikr) should not be mixed with ordinary permissible speech in gatherings of dhikr, except out of necessity, and only to the extent of that necessity. This is based on the Prophet's (peace be upon him) saying regarding circumambulation (Tawaf): "Tawaf around the Kaaba is prayer, so minimize speech."

Imam Nawawi said: "Speaking during Tawaf is permissible; it neither invalidates it nor is it disliked. However, it is better to refrain from it unless it is for a good purpose." As for ordinary permissible conversation in the mosque, it is permissible as long as it is not mixed with dhikr or does not disturb someone engaged in dhikr or prayer. However, if it is at a high volume or involves disputes, it is reprehensible, based on the Prophet's (peace be upon him) saying: "In the latter days, there will be people who sit in the mosques in circles, their imam being the worldly life. Do not sit with them, for Allah has no need of them."

The Prophet (peace be upon him) used to sit after the dawn prayer, and the Companions would talk about matters of the pre-Islamic era, laughing and smiling.