بُلُوغُ الْمَرَامِ
Bulugh al-Maram 456
The Book of Prayer
وَعَنْ جَابِرٍ قَالَ: { دَخَلَ رَجُلٌ يَوْمَ اَلْجُمُعَةِ, وَالنَّبِيُّ - صلى الله عليه وسلم -يَخْطُبُ . فَقَالَ: "صَلَّيْتَ?" قَالَ: لَا. قَالَ: "قُمْ فَصَلِّ رَكْعَتَيْنِ" } مُتَّفَقٌ عَلَيْهِ . [1] .
Narrated Jabir (RA): A man entered the mosque on a Friday when the Prophet (ﷺ) was delivering the Khutbah (religious talk, sermon) and he [the Prophet (ﷺ)] said, "Have you prayed? He replied, "No." He [the Prophet (ﷺ)] said, "Stand and pray two Rak'at." [Agreed upon].
Sunnah.com reference: Book 2, Hadith 376