Abu Hurairah reported,

From Muhammad, the Messenger of Allah ﷺ, several hadiths were mentioned, among them that the Messenger of Allah ﷺ said, "When one of you leads the people in prayer, let him keep it short, for among them are the elderly and the weak. But when he prays alone, let him prolong his prayer as much as he wishes."

Muslim 1047

Sahih

حدثنا ابن رافع حدثنا عبد الرزاق حدثنا معمر عن همام بن منبه قال هذا ما حدثنا

أبو هريرة

عن محمد رسول الله ﷺ فذكر أحاديث منها وقال رسول الله ﷺ إذا ما قام أحدكم للناس فليخفف الصلاة فإن فيهم الكبير وفيهم الضعيف وإذا قام وحده فليطل صلاته ما شاء

مسلم 1047صحيح
Contents
Reference
Commentary
Ayat
Collection
Sahih Muslim
Book
Prayer
Chapter
Commanding the imams to shorten the prayer while completing it
Numbering
Darussalam 1047
Muslim 1047