Genesis 31:29

It is in the power of my hand to do you hurt; but the God of your father spake unto me yesternight, saying, Take thou heed that thou speak not to Jacob either good or bad. The band which Laban had brought along was indeed large enough to inflict severe harm upon Jacob, and it was only the fear of God's punishment which deterred him from following his inclination. At this point the animosity of Laban evidently caused him to forget all prudence and to betray his bitterness and his real intention.