It is narrated from Hazrat Abu Saeed (may Allah be pleased with him) that once the Prophet (peace and blessings be upon him) saw spit or filth fallen in the direction of the qiblah in the mosque. The Prophet (peace and blessings be upon him) cleaned it with a pebble and, forbidding spitting in front or to the right side, said that one should spit to the left side or beneath one's foot.