The dust of our ground with the saliva of any one of us would serve as a means whereby our illness would be cured with the sanction of Allah. This hadith has been transmitted on the authority of Ibn Abu Shaiba and Zubair with a slight variation of wording. (Using translation from Muslim 2194)
أَنَّ رَسُولَ اللَّهِ ﷺ كَانَ إِذَا اشْتَكَى الْإِنْسَانُ الشَّيْءَ مِنْهُ أَوْ كَانَتْ بِهِ قَرْحَةٌ أَوْ جُرِحَ قَالَ النَّبِيُّ ﷺ بِإِصْبَعِهِ هَكَذَا وَوَضَعَ سَبَّابَتَهُ بِالْأَرْضِ ثُمَّ رَفَعَهَا «بِسْمِ اللَّهِ تُرْبَةُ أَرْضِنَا بِرِيقَةِ بَعْضِنَا يُشْفَى سَقِيمُنَا بِإِذْنِ رَبِّنَا»