Sahih al-Bukhari 341
Sahih al-Bukhari · Book 7: Rubbing hands and feet with dust (Tayammum) · Tayammum is for the hands and the face
Narrated `Abdur Rahman bin Abza:
حَدَّثَنَا مُحَمَّدُ بْنُ كَثِيرٍ ، أَخْبَرَنَا شُعْبَةُ ، عَنِ الْحَكَمِ ، عَنْ ذَرٍّ ، عَنِ ابْنِ عَبْدِ الرَّحْمَنِ بْنِ أَبْزَى ، عَنْ عَبْدِ الرَّحْمَنِ ، قَالَ قَالَ عَمَّارٌ لِعُمَرَ تَمَعَّكْتُ فَأَتَيْتُ النَّبِيَّ صلى الله عليه وسلم فَقَالَ " يَكْفِيكَ الْوَجْهُ وَالْكَفَّانِ " .
`Ammar said to `Umar "I rolled myself in the dust and came to the Prophet (ﷺ) who said, 'Passing dusted hands over the face and the backs of the hands is sufficient for you.' "