If you have understanding, answer your neighbor; if not, lay your hand upon your mouth.
LXX
Sirach 5:12
If thou hast understanding, answer thy neighbour; if not, lay thy hand upon thy mouth.
Parallel Translations
If thou hast understanding, answer thy neighbour; if not, lay thy hand upon thy mouth.
If you have understanding, answer your neighbor; but if not, put your hand over your mouth.