If you finish reciting in a quiet prayer and the imam has not finished
Machine translationRead the Arabic original
Question : He says: If you pray behind the imam in a quiet prayer and you finish the surah while the imam has not finished, Honorable Shaykh, what should I do?
Answer : You recite, you recite another surah until the imam bows. All right.
Answer : You recite, you recite another surah until the imam bows. All right.
Source
قناة «فضيلة الشيخ محمد بن صالح العثيمين»، 293- إذا انتهيت من القراءة في الصلاة السرية والإمام لم ينتهي /سؤال على الهاتف /ابن عثيمين — youtube.com
The Arabic text is a machine transcription of the audio recording.