四分律比丘含注戒本 2.712

2.712

聽者，屏聽他語。若聽彼語，從道至非道，從高至下，若反上句，往而聞者。

("listening" means secretly eavesdropping on another's words; whether he listens to their words going from a proper place to an improper place, from high to low, or vice versa, going there and hearing them)