A man came to ʿUmar bin Al-Khattab and said, "I became Junub but no water was available." ʿAmmar bin Yasir said to ʿUmar, "Do you remember that you and I (became Junub while both of us) were together on a journey and you didn't pray but I rolled myself on the ground and prayed? I informed the Prophet ﷺ about it and he said, 'It would have been sufficient for you to do like this.' The Prophet then stroked lightly the earth with his hands and then blew off the dust and passed his hands over his face and hands."  

عَمَّارُ بْنُ يَاسِرٍ لِعُمَرَ بْنِ الْخَطَّابِ أَمَا تَذْكُرُ أَنَّا كُنَّا فِي سَفَرٍ أَنَا وَأَنْتَ فَأَمَّا أَنْتَ فَلَمْ تُصَلِّ وَأَمَّا أَنَا فَتَمَعَّكْتُ فَصَلَّيْتُ فَذَكَرْتُ لِلنَّبِيِّ ﷺ فَقَالَ النَّبِيُّ ﷺ إِنَّمَا كَانَ يَكْفِيكَ هَكَذَا فَضَرَبَ النَّبِيُّ ﷺ بِكَفَّيْهِ الأَرْضَ وَنَفَخَ فِيهِمَا ثُمَّ مَسَحَ بِهِمَا وَجْهَهُ وَكَفَّيْهِ