The Messenger of Allah ﷺ saw spittle on the wall towards Qibla, and scratched it away and then turning to the people said: When any one of you prays, he must not spit in front of him, for Allah is in front of him when he is engaged in prayer.  

أَنَّ رَسُولَ اللَّهِ ﷺ رَأَى بُصَاقًا فِي جِدَارِ الْقِبْلَةِ فَحَكَّهُ ثُمَّ أَقْبَلَ عَلَى النَّاسِ فَقَالَ إِذَا كَانَ أَحَدُكُمْ يُصَلِّي فَلاَ يَبْصُقْ قِبَلَ وَجْهِهِ فَإِنَّ اللَّهَ قِبَلَ وَجْهِهِ إِذَا صَلَّى  

Ibn Umar reported that the Messenger of Allah ﷺ saw sputum sticking to the Qibla wall of the mosque, the rest of the hadith is the same.  

عَنِ النَّبِيِّ ﷺ أَنَّهُ رَأَى نُخَامَةً فِي قِبْلَةِ الْمَسْجِدِ إِلاَّ الضَّحَّاكَ فَإِنَّ فِي حَدِيثِهِ نُخَامَةً فِي الْقِبْلَةِ بِمَعْنَى حَدِيثِ مَالِكٍ  

The Apostle of Allah ﷺ saw sputum sticking to the Qibla of the mosque. He scratched it off with a pebble and then forbade spitting on the right side or in front, but (it is permissible) to spit on the left side or under the left foot.  

أَنَّ النَّبِيَّ ﷺ رَأَى نُخَامَةً فِي قِبْلَةِ الْمَسْجِدِ فَحَكَّهَا بِحَصَاةٍ ثُمَّ نَهَى أَنْ يَبْزُقَ الرَّجُلُ عَنْ يَمِينِهِ أَوْ أَمَامَهُ وَلَكِنْ يَبْزُقُ عَنْ يَسَارِهِ أَوْ تَحْتَ قَدَمِهِ الْيُسْرَى  

Abu Huraira and Abu Sa'id narrated that the Messenger of Allah ﷺ saw sputum, and the rest of the hadith is the same.  

أَنَّ رَسُولَ اللَّهِ ﷺ رَأَى نُخَامَةً بِمِثْلِ حَدِيثِ ابْنِ عُيَيْنَةَ  

The Apostle of Allah (may, peace be upon him) saw spittle or snot or sputum, sticking to the wall towards Qibla and scratched it off.  

أَنَّ النَّبِيَّ ﷺ رَأَى بُصَاقًا فِي جِدَارِ الْقِبْلَةِ أَوْ مُخَاطًا أَوْ نُخَامَةً فَحَكَّهُ  

How Is it that someone amongst you stands before his Lord and then spits out in front of Him? Does any one of you like that he should be made to stand in front of someone and then spit at his face? So when any one of you spits, he must spit on his left side under his foot. But if he does not find (space to spit) he should do like this. Qasim (one of the narrators) spat in his cloth and then folded it and rubbed it.  

أَنَّ رَسُولَ اللَّهِ ﷺ رَأَى نُخَامَةً فِي قِبْلَةِ الْمَسْجِدِ فَأَقْبَلَ عَلَى النَّاسِ فَقَالَ مَا بَالُ أَحَدِكُمْ يَقُومُ مُسْتَقْبِلَ رَبِّهِ فَيَتَنَخَّعُ أَمَامَهُ أَيُحِبُّ أَحَدُكُمْ أَنْ يُسْتَقْبَلَ فَيُتَنَخَّعَ فِي وَجْهِهِ فَإِذَا تَنَخَّعَ أَحَدُكُمْ فَلْيَتَنَخَّعْ عَنْ يَسَارِهِ تَحْتَ قَدَمِهِ فَإِنْ لَمْ يَجِدْ فَلْيَقُلْ هَكَذَا وَوَصَفَ الْقَاسِمُ فَتَفَلَ فِي ثَوْبِهِ ثُمَّ مَسَحَ بَعْضَهُ عَلَى بَعْضٍ  

I perceive as if I am looking at the Messenger of Allah ﷺ folding up a part of his cloth with another one.  

عَنِ النَّبِيِّ ﷺ نَحْوَ حَدِيثِ ابْنِ عُلَيَّةَ وَزَادَ فِي حَدِيثِ هُشَيْمٍ قَالَ أَبُو هُرَيْرَةَ كَأَنِّي أَنْظُرُ إِلَى رَسُولِ اللَّهِ ﷺ يَرُدُّ ثَوْبَهُ بَعْضَهُ عَلَى بَعْضٍ  

The Messenger of Allah ﷺ said: When any one of you is engaged in prayer, he is holding intimate conversation with his Lord, so none of you must spit in front of him, or towards his right side, but towards his left side under his foot.  

قَالَ رَسُولُ اللَّهِ ﷺ إِذَا كَانَ أَحَدُكُمْ فِي الصَّلاَةِ فَإِنَّهُ يُنَاجِي رَبَّهُ فَلاَ يَبْزُقَنَّ بَيْنَ يَدَيْهِ وَلاَ عَنْ يَمِينِهِ وَلَكِنْ عَنْ شِمَالِهِ تَحْتَ قَدَمِهِ  

The Messenger of Allah ﷺ said: Spitting in a mosque is a sin, and its expiation is that it should be buried.  

قَالَ رَسُولُ اللَّهِ ﷺ الْبُزَاقُ فِي الْمَسْجِدِ خَطِيئَةٌ وَكَفَّارَتُهَا دَفْنُهَا  

I asked Qatada about spitting, in the mosque. He said: I heard Anas b. Malik say: I heard the Messenger of Allah ﷺ say: Spitting in the mosque is a sin, and its expiation is that it should be buried.  

سَمِعْتُ رَسُولَ اللَّهِ ﷺ يَقُولُ التَّفْلُ فِي الْمَسْجِدِ خَطِيئَةٌ وَكَفَّارَتُهَا دَفْنُهَا  

The Apostle of Allah ﷺ said: The deeds of my people, good and bad, were presented before me, and I found the removal of something objectionable from the road among their good deeds, and the sputum mucus left unburied in the mosque among their evil deeds.  

عَنِ النَّبِيِّ ﷺ قَالَ عُرِضَتْ عَلَىَّ أَعْمَالُ أُمَّتِي حَسَنُهَا وَسَيِّئُهَا فَوَجَدْتُ فِي مَحَاسِنِ أَعْمَالِهَا الأَذَى يُمَاطُ عَنِ الطَّرِيقِ وَوَجَدْتُ فِي مَسَاوِي أَعْمَالِهَا النُّخَاعَةَ تَكُونُ فِي الْمَسْجِدِ لاَ تُدْفَنُ  

I said prayer with the Messenger of Allah ﷺ and saw him spitting and rubbing it off with his shoe.  

صَلَّيْتُ مَعَ رَسُولِ اللَّهِ ﷺ فَرَأَيْتُهُ تَنَخَّعَ فَدَلَكَهَا بِنَعْلِهِ  

'Abdullah b. Shakhkhir narrated it on the authority of his father that he said prayer with the Messenger of Allah ﷺ, and he spat and then rubbed it off with his left shoe.  

أَنَّهُ صَلَّى مَعَ النَّبِيِّ ﷺ قَالَ فَتَنَخَّعَ فَدَلَكَهَا بِنَعْلِهِ الْيُسْرَى