A short one, when you cannot manage more
Said by people in the Qur'an who had nothing left to argue with.
إِنَّهُۥ كَانَ فَرِيقٌ مِّنْ عِبَادِى يَقُولُونَ رَبَّنَآ ءَامَنَّا فَٱغْفِرْ لَنَا وَٱرْحَمْنَا وَأَنتَ خَيْرُ ٱلرَّٰحِمِينَ
Rabbanā āmannā fa-ghfir lanā wa-rḥamnā wa anta khayru-r-rāḥimīn.
Indeed, there was a party of My servants who said, 'Our Lord, we have believed, so forgive us and have mercy upon us, and You are the best of the merciful.'
Source
The Qur'an · 23:109
Qur'an
- Qur'anic text in the Uthmani script via Quran.com; translation: Saheeh International