口は災いのもと The Mouth is the Origin of Disasters

Japanese proverbs

Transparent

 

口は災いのもと
(or 口は禍のもと)
The mouth is the origin of disasters

口は禍のもと
Japanese
くち は わざわい の もと kuchi wa wazawai no moto
Literal
The mouth is the origin of disasters.
English Equivalent
The mouth is the gate of misfortune.
Notes

A quick Google search seems to give 災い a lead