The Messenger of Allah ﷺ used to instruct us to keep the prayer brief, yet he himself would lead us in prayer reciting Surah as-Saffat.
أخبرنا إسمعيل بن مسعود قال حدثنا خالد بن الحارث عن ابن أبي ذئب قال أخبرني الحارث بن عبد الرحمن عن سالم بن عبد الله
كان رسول الله ﷺ يأمر بالتخفيف ويؤمنا بالصافات
[Its isnad is hasan] Ahmad reported it, 2/26, 40, 157, from the hadith of Ibn Abu Dhib through this route, and it is in Al-Kubra, no. 900, and Ibn Khuzayma graded it sahih, no. 1606. Harith bin Abdul-Rahman is Amiri, Madani, Qurashi.