Sunan Abi Dawud, Book 1, Hadith 324 (USC-MSA)

Ibn 'Abd al-Rahman b. Abza reported on the authority of his father this incident from 'Ammar. He said: This would have been enough for you, and the Prophet struck the ground with his hand. He then blew it and wiped with it his face and hands. Being doubtful Salamah said: I do not know (whether he wiped) up to the elbows or the wrists.

حَدَّثَنَا مُحَمَّدُ بْنُ بَشَّارٍ، حَدَّثَنَا مُحَمَّدٌ، - يَعْنِي ابْنَ جَعْفَرٍ - أَخْبَرَنَا شُعْبَةُ، عَنْ سَلَمَةَ، عَنْ ذَرٍّ، عَنِ ابْنِ عَبْدِ الرَّحْمَنِ بْنِ أَبْزَى، عَنْ أَبِيهِ، عَنْ عَمَّارٍ، بِهَذِهِ الْقِصَّةِ فَقَالَ ‏ "‏ إِنَّمَا كَانَ يَكْفِيكَ ‏" ‏ ‏.‏ وَضَرَبَ النَّبِيُّ صلى الله عليه وسلم بِيَدِهِ إِلَى الأَرْضِ ثُمَّ نَفَخَ فِيهَا وَمَسَحَ بِهَا وَجْهَهُ وَكَفَّيْهِ شَكَّ سَلَمَةُ وَقَالَ لاَ أَدْرِي فِيهِ إِلَى الْمِرْفَقَيْنِ ‏.‏ يَعْنِي أَوْ إِلَى الْكَفَّيْنِ ‏.‏

sunnah.com