John Calvin Commentary 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 heed to thyself that thou speak not to Jacob either good or bad." — Genesis 31:29 (ASV)

It is in the power of my hand. The Hebrew phrase is different: “my hand is to power;” yet the meaning is clear, that Laban declares he is ready to take vengeance. Some interpret the words as follows: “my hand is to God;” but from other places it appears that the word אל (el) is taken for power.

But Laban, inflated with foolish boasting, contradicts himself. Since he had been forbidden by God to attempt anything against Jacob, where was the power of which he boasted? We see, therefore, that he rushes headlong by a blind impulse, as if he could do anything against the purpose of God as he pleased.

For when he perceives that God is opposed to him, he still does not hesitate to glory in his own strength. And why is this, unless it was because he aimed at being superior to God?

Finally, pride is always the companion of unbelief, so that unbelievers, although vanquished, still do not cease to rise up impetuously against God. To this they add another sin: they complain of being unjustly oppressed by God.

But the God of your father. Why does he not also acknowledge God as his own God, unless it is because Satan had already so fascinated his mind that he chose instead to wander in darkness rather than turn to the light presented before him?

Willingly or unwillingly, he is compelled to yield to the God of Abraham; and yet he deprives Him of the glory that is due by retaining those fictitious deities by which he had been deceived.

We see, then, that the ungodly, even when they have had proof of the power of God, still do not entirely submit themselves to His authority. Therefore, when God reveals Himself to us, we must also seek from heaven the spirit of meekness that will bend and subdue us to obedience to Him.