“The Prophet ﷺ said: ‘When you perform prayer, do not spit in front of you or to your right, but spit to your left or beneath your feet.’”  

النَّبِيُّ ﷺ إِذَا صَلَّيْتَ فَلاَ تَبْزُقَنَّ بَيْنَ يَدَيْكَ وَلاَ عَنْ يَمِينِكَ وَلَكِنِ ابْزُقْ عَنْ يَسَارِكَ أَوْ تَحْتَ قَدَمِكَ  

“What is wrong with one of you that he stands facing Him (meaning his Lord) and spits in front of Him? Would anyone like to be faced by someone who spits in his face? If anyone of you needs to spit, then let him spit to his left, or let him do like this in his garment.” Then Ismail (Abu Bakr bin Abu Shuaibah) showed me how he spat in his garment then rubbed it.  

أَنَّ رَسُولَ اللَّهِ ﷺ رَأَى نُخَامَةً فِي قِبْلَةِ الْمَسْجِدِ فَأَقْبَلَ عَلَى النَّاسِ فَقَالَ مَا بَالُ أَحَدِكُمْ يَقُومُ مُسْتَقْبِلَهُ يَعْنِي رَبَّهُ فَيَتَنَخَّعُ أَمَامَهُ أَيُحِبُّ أَحَدُكُمْ أَنْ يُسْتَقْبَلَ فَيُتَنَخَّعَ فِي وَجْهِهِ إِذَا بَزَقَ أَحَدُكُمْ فَلْيَبْزُقَنَّ عَنْ شِمَالِهِ أَوْ لِيَقُلْ هَكَذَا فِي ثَوْبِهِ ثُمَّ أَرَانِي إِسْمَاعِيلُ يَبْزُقُ فِي ثَوْبِهِ ثُمَّ يَدْلُكُهُ  

“O Shabath! Do not spit in front of you, for the Messenger of Allah ﷺ used to forbid that, and he said: ‘When a man stands up to perform prayer, Allah turns His Face towards him until he turns away or he commits an evil Hadath.’”* * In Injah Al-Hajah, 'Abdul-Ghani Dehlawi said: "Meaning he does a matter that negates the Khushu'(submissiveness) and attentiveness of his prayer. Or, the meaning of Hadath is invalidating the ablution. The only reason that he described it as 'evil' is because in most cases, its occurrence during prayer is from Shaitan."  

يَا شَبَثُ لاَ تَبْزُقْ بَيْنَ يَدَيْكَ فَإِنَّ رَسُولَ اللَّهِ ﷺ كَانَ يَنْهَى عَنْ ذَلِكَ وَقَالَ إِنَّ الرَّجُلَ إِذَا قَامَ يُصَلِّي أَقْبَلَ اللَّهُ عَلَيْهِ بِوَجْهِهِ حَتَّى يَنْقَلِبَ أَوْ يُحْدِثَ حَدَثَ سُوءٍ  

It was narrated from Anas bin Malik that the Messenger of Allah ﷺ spat on his garment while he was performing prayer, then he rubbed it.  

أَنَّ رَسُولَ اللَّهِ ﷺ بَزَقَ فِي ثَوْبِهِ وَهُوَ فِي الصَّلاَةِ ثُمَّ دَلَكَهُ