Proverbi 30:32

Se hai fatto stoltezza nell'alzarti, o se hai pensato male, mettiti la mano sulla bocca.

If thou hast done foolishly (or, hast been foolish) in lifting up thyself - through pride and insolence. The following clause --

If thou hast thought evil - or hast devised evil, implies that the action supposed is one begun, not completed.

(Lay) thine hand upon thy mouth - (Giobbe 21:5; Giobbe 40:4.) Abstain from all excuse or defense of the past; and curb thyself in silence from speaking and still more from going on to do that evil which thou thoughtest.