(36) باب لِيَبْزُقْ عَنْ يَسَارِهِ، أَوْ تَحْتَ قَدَمِهِ الْيُسْرَى
Narrated Anas bin Malik:
The Prophet (ﷺ) said, "A faithful believer while in prayer is speaking in private to his Lord, so he should neither spit in front of him nor to his right side but he could spit either on his left or under his foot."
Reference: Sahih al-Bukhari 413
In-book reference: Book 8, Hadith 63
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 1, Book 8, Hadith 405