an ounce of discretion is worth a pound of wit
It is much better to know when to refrain from speaking than to have the ability to make jokes or witty remarks, which may come at an inappropriate time or be about an inappropriate subject. Now's not the time for one of your lewd jokes, Frank. Didn't anyone ever teach you that an ounce of discretion is worth a pound of wit?
ounce of discretion is worth a pound of wit
Prov. Knowing when to refrain from making jokes is better than being able to make jokes all the time. Mabel makes fun of everybody, regardless of whether or not she hurts their feelings. Someone should tell her that an ounce of discretion is worth a pound of wit.