The Apostle of Allah (ﷺ) used to recite in the morning prayer" Qaf. By the Glorious Quran." and his prayer afterward shortened.
Sahih Muslim Book 4, Hadith 189
← Previous Hadith "And the tall palm trees having flower spikes piled one above another (l. 10) or perhaps Surah Qaf."

Sahih Muslim Book 4, Hadith 188 Next Hadith → He (the Holy Prophet) shortened the prayer and he did not pray like these people then, and he informed me that the Messenger of Allah (ﷺ) used to recite" Qaf. By the (Glorious) Qur'an," and a passage of similar length.

Sahih Muslim Book 4, Hadith 190