AbuSa'id said: I saw Wathilah ibn al-Asqa' in the mosque of Damascus. He spat at the mat and then rubbed it with his foot. He was asked: Why did you do so? He said: Because I saw the Messenger of Allah ﷺ doing so. (Using translation from Abū Dāʾūd 484)

لَوْلَا أَنِّي رَأَيْتُ رَسُولَ اللهِ ﷺ يَفْعَلُ ذَلِكَ مَا فَعَلْتُ