وَحَدَّثَنِي حَرْمَلَةُ بْنُ يَحْيَى، أَخْبَرَنَا ابْنُ وَهْبٍ، أَخْبَرَنِي يُونُسُ، عَنِ ابْنِ شِهَابٍ، حَدَّثَنِي سَالِمُ بْنُ عَبْدِ اللَّهِ، عَنْ أَبِيهِ، ‏.‏ أَنَّ عُمَرَ بْنَ الْخَطَّابِ، بَيْنَا هُوَ يَخْطُبُ النَّاسَ يَوْمَ الْجُمُعَةِ دَخَلَ رَجُلٌ مِنْ أَصْحَابِ رَسُولِ اللَّهِ صلى الله عليه وسلم فَنَادَاهُ عُمَرُ أَيَّةُ سَاعَةٍ هَذِهِ فَقَالَ إِنِّي شُغِلْتُ الْيَوْمَ فَلَمْ أَنْقَلِبْ إِلَى أَهْلِي حَتَّى سَمِعْتُ النِّدَاءَ فَلَمْ أَزِدْ عَلَى أَنْ تَوَضَّأْتُ ‏.‏ قَالَ عُمَرُ وَالْوُضُوءَ أَيْضًا وَقَدْ عَلِمْتَ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم كَانَ يَأْمُرُ بِالْغُسْلِ ‏.‏

'Abdullah (b. 'Umar) reported from his father that while he was addressing the people on Friday (sermon), a person, one of the Companions of the Messenger of Allah (PBUH), entered (the mosque). Umar said to him loudly: What is this hour (for attending the prayer)? He said: I was busy today and I did not return to my house when I heard the call (to Friday prayer), and I did no more but performed ablution only. Upon this Umar said: just ablution! You know that the Messenger of Allah (PBUH) commanded (us) to take a bath (on Friday). Translation Not Available

Book reference: Sahih Muslim Book 7 Hadith 1836
Web reference: Sahih Muslim Book 4 Hadith 845 a