According to popular belief, thunder is a god of the sky (Thiên Lôi); lightning is a god named La Sát whose role is to punish the wicked and the bad spirits striking at trees, their dwellings.

Ông Sấm bà Sét (Mr. Thunder, Mrs. Thunderbolt): designating persons of violent character. Đánh trống qua cửa nhà sấm (to beat a drum before the door of Mr. Thunder): a vain person.