Abu Huraira said that while a man was praying letting his lower garment trail, God’s Messenger said to him, “Go and perform ablution.” After he had gone to perform ablution and returned a man asked God’s Messenger why he had ordered him to perform ablution, and he said “He was praying with his lower garment trailing, and God does not accept the prayer of a man who lets his lower garment trail.”
Salama b. al-Akwa‘said that he told God’s Messenger he was a man who went out hunting, and asked whether he might pray in a single shirt. He replied, “Yes, but fasten it, even if it should be with a thorn.”
Abu Dawud transmitted it and Nasa’i transmitted something similar.
‘Uqba b. ‘Amir said that God’s Messenger was presented with a silk gown which he put on and wore while praying. Then when he withdrew he pulled it off vigorously as though he disapproved of it, saying, “This is not fitting for the pious.”