Mishkat al-Masabih
Mishkat al-Masabih 2274
وَعَنْهُ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «مَا جَلَسَ قَوْمٌ مَجْلِسًا لَمْ يَذْكُرُوا اللَّهَ فِيهِ وَلَمْ يُصَلُّوا عَلَى نَبِيِّهِمْ إِلَّا كَانَ عَلَيْهِمْ تِرَةً فَإِنْ شَاءَ عَذَّبَهُمْ وَإِنْ شَاءَ غَفَرَ لَهُمْ» . رَوَاهُ التِّرْمِذِيُّ
Unreviewed translation. All hadiths in this collection are available in five languages. Titles and introductions may remain in Arabic.
Abu Hurayrah reported that the Messenger of God (peace be upon him) said: ‘No people sit in a gathering without remembering God and invoking blessings upon their Prophet without it becoming a source of regret for them. If He wills, He punishes them; and if He wills, He forgives them.’ Al-Tirmidhi transmitted it. The Arabic source grades it sahih (al-Albani).
Notes and open questions — unreviewed
The Arabic uses تِرَةٌ, denoting loss or regret.