The princes refrained talking - As a mark of respect, or in awe of his presence.
And laid their hand on their mouth - To lay the finger or the hand on the mouth is every where an action expressive of silence or respect; Notes, Job 21:5. “In one of the subterranean vaults of Egypt, where the mummies lie buried, they found in the coffin an embalmed body of a woman, before which was placed a figure of wood, representing a youth on his knees, laying a finger on his mouth, and holding in his other hand a sort of chafing dish, which was placed on his head, and in which, without doubt, had been some perfumes.” Maillet.