The common saying is “Silence is golden” — it means it’s often better to speak less, especially when too much talking can cause trouble or reveal too much.

A few related sayings are:

  • “Talk is cheap.”
  • “Loose lips sink ships.”
  • “When you have nothing to say, say nothing.”

If you meant a phrase for someone who talks too much, “talks a lot” or “talks your ear off” are common expressions.