俱舍論記 15.170

15.170

「遣三使已至俱時究竟」者，釋。如遣三使，一殺、一盜、一行誑，己自行邪欲。此四俱時究竟業道，名現等四。

"Having dispatched three messengers … brought to completion at the same time": the explanation. For example, dispatching three messengers: one kills, one steals, and one practices deceit, while one personally commits sexual misconduct oneself. When these four courses of action are completed at the same time, they are called the four [karmas], present and so forth.