Full Sharh — Mishkat al-Masabih 695
وَعَن أنس: رَأَى النَّبِيُّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ نُخَامَةً فِي الْقِبْلَةِ فَشَقَّ ذَلِكَ عَلَيْهِ حَتَّى رُئِيَ فِي وَجهه فَقَامَ فحكه بِيَدِهِ فَقَالَ: «إِنَّ أَحَدَكُمْ إِذَا قَامَ فِي صلَاته فَإِنَّمَا يُنَاجِي ربه أَو إِن رَبَّهُ بَيْنَهُ وَبَيْنَ الْقِبْلَةِ فَلَا يَبْزُقَنَّ أَحَدُكُمْ قِبَلَ قِبْلَتِهِ وَلَكِنْ عَنْ يَسَارِهِ أَوْ تَحْتَ قَدَمِهِ» ثُمَّ أَخَذَ طَرَفَ رِدَائِهِ فَبَصَقَ فِيهِ ثُمَّ رَدَّ بَعْضَهُ عَلَى بَعْضٍ فَقَالَ: «أَوْ يفعل هَكَذَا» . رَوَاهُ البُخَارِيّ
English Translation
Anas said that the Prophet saw some mucus in the direction of the qibla and his displeasure was apparent in his face, so he got up, scraped it with his hand and said, “When one of you gets up to pray, he is holding intimate converse only with his Lord, and his Lord is between him and the qibla, so none of you must spit in the direction of the qibla, but towards his left side, or under his foot.” Then he took the end of his cloak, spat in it, folded it up and said, “Or he may do thus.” Bukhari transmitted it.
Source
Mishkat al-Masabih(مشكاة المصابيح)
Prayer
Hadith Number
695