Al-Adab Al-Mufrad, Book 55, Hadith 1303 (English) ⓘ

Abu Hurayra said, "When someone spits in the presence of people, let him catch it with his palms so that his spit does not fall on the ground. When he fasts, he should oil his palm so that the trace of the fast is not seen on him."

حَدَّثَنَا مُوسَى، عَنْ حَمَّادِ بْنِ سَلَمَةَ، قَالَ‏:‏ أَخْبَرَنَا ثَابِتٌ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ عَيَّاشٍ الْقُرَشِيِّ، عَنْ أَبِي هُرَيْرَةَ قَالَ‏:‏ إِذَا تَنَخَّعَ بَيْنَ يَدَيِ الْقَوْمِ فَلْيُوَارِ بِكَفَّيْهِ حَتَّى تَقَعَ نُخَاعَتُهُ إِلَى الأَرْضِ، وَإِذَا صَامَ فَلْيَدَّهِنْ، لاَ يُرَى عَلَيْهِ أَثَرُ الصَّوْمِ‏.‏