An old proverb meaning that speaking may bring trouble and sometimes it's better to remain silent; a warning against careless remarks.
物言えば唇寒し秋の風と言うから、余計なことは言わない方がいい場面だ。
They say 'if you speak you'll feel a chill on your lips like an autumn wind,' so this is a situation where it's better not to say anything unnecessary.
この件については黙っていた方が安全だ。物言えば唇寒し秋の風だ。
It's safer to keep quiet about this matter. Silence is golden, as the proverb goes.