法苑珠林 94.39

94.39

塔前眾僧前和尚阿闍梨前。不得張口大洟唾著地。若欲洟唾當屏猥處。莫令人惡賤。是名涕唾法。

In front of a stūpa, in front of the assembled monks, and in front of an upādhyāya or ācārya, one must not open the mouth and spit out large amounts of phlegm or spittle onto the ground. If one wishes to spit phlegm or spittle, one should go to a secluded, coarse place, not causing others to feel disgust and contempt. This is called the rule for phlegm and spittle."