Once the Prophet (ﷺ) prayed on a Khamisa with marks on it and said, "The marks on it diverted my attention, take this Khamisa to Abu Jahm and bring an Inbijaniya (from him.)"
Sahih al-Bukhari Book 10, Hadith 146
← Previous Hadith I asked Allah's Messenger (ﷺ) about looking hither and thither in prayer. He replied, "It is a way of stealing by which Satan takes away (a portion) from the prayer of a person."

Sahih al-Bukhari Book 10, Hadith 145 Next Hadith → The Prophet (ﷺ) saw expectoration in the direction of the Qibla of the mosque while he was leading the prayer, and scratched it off. After finishing the prayer, he said, "Whenever any of you is in prayer he should know that Allah is in front of him. So none should spit in front of him in the prayer."

Sahih al-Bukhari Book 10, Hadith 147