In another narration of Muslim:

"He (ﷺ) sent an announcer to announce: The prayer is (to be offered) in congregation".

وَفِي رِوَايَةٍ لَهُ: فَبَعَثَ مُنَادِيًا يُنَادِي: اَلصَّلَاةُ جَامِعَةٌ [1]‏ .‏