Abu Hurairah reported,

The Prophet ﷺ said, "No people sit in a gathering in which they do not remember Allah عز وجل and send blessings upon the Prophet, except that it will be a source of regret for them on the Day of Resurrection, even if they enter Paradise for their reward."

Azami 10783

Sahih

عن أبي هريرة

عن النبي ﷺ قال: ما قعد قوم مقعدا لا يذكرون فيه الله عز وجل، ويصلون على النبي إلا كان عليهم حسرة يوم القيامة وإن دخلوا الجنة للثواب.

الأعظمي 10783صحيح
Contents
Reference
Commentary
Ayat
Collection
Jami al-Kamil
Book
Supplications, remembrances, and prayer upon the chosen Prophet ﷺ
Chapter
Supplications
Section
Dislike for a man to get up from his sitting without remembering Allah in it
Numbering
Jami al-Kamil 10783 (2nd edition)
Azami 10783