“The wise don’t make a show of their knowledge, but fools broadcast their foolishness.” (Proverbs 12:23)
Not Proverbs again, surely? But, yes, here is another verse from that book of wisdom. I don’t need to add anything here. We all know someone like this: he/she gets themselves into trouble by speaking when they should be listening. They can’t keep their moth shut – even when they have no clue what they’re on about.