佛說處處經 1.9

1.9

「佛不著履，有三因緣：一者、使行者少欲；二者、現足下輪；三者、令人見之歡喜。

"That the Buddha does not wear sandals is due to three nidānas: first, to cause practitioners to have few desires; second, to display the wheels beneath his feet; third, to cause people who see them to rejoice.