Genesis 27:33
And Isaac trembled very exceedingly, and said, Who? where is he that hath taken venison, and brought it me, and I have eaten of all before thou camest, and have blessed him? yea, and he shall be blessed. And Isaac trembled very exceedingly, and said, Who? where is he that hath taken venison, and brought it me, and I have eaten of all before thou camest, and have blessed him? yea, and he shall be blessed.
Isaac had meant his blessing for Esau, but Jacob secured it by bringing venison and presenting himself as his brother, and the trembling recorded in the verse is Isaac's discovery of what had taken place. Once spoken the blessing could not be recalled, and Isaac declared that it would stay upon Jacob. That confirmation came because Isaac saw God's providence overruling what he himself had tried to prevent, remembered God's earlier words concerning Jacob, and discerned the Spirit's inspiration in the blessing even though Jacob had sinned by deception to gain it. He was further convinced afterward, by the unfolding course of Esau and of Jacob, that the blessing rightly belonged to Jacob.
The blessing attached to the firstborn did not in itself assure prosperity, for God could bless Esau or send him adversity according to his conduct, while Jacob could receive God's blessing through righteous living even without the privileges commonly given to the firstborn. Jacob's fraud was sin that called for repentance, which he afterward exercised, and without that repentance he would not have been heard when he later pleaded with God nor mercifully preserved. That deed reacted upon him, reaping its harvest in his brother's hatred, in twenty years of exile during which he was himself wronged and defrauded until compelled to find safety in flight, and in a second harvest when the evils of his own character reappeared in his sons. In this is shown that what a person does is the fruit of what he is, and that life's experiences are the ripening of his own thoughts and deeds. The same sin brought him danger and self-reproach when he returned home years later.
Esau's deep distress on learning his loss came too late to undo his earlier reckless sale of his birthright. His case warns that those who exchange their heavenly inheritance for selfish pleasure and harmful desires will regret that choice at the judgment yet find no reversal then, even if they seek it with tears. The same deceptive dealing reappears among those in high places of trust who show partiality and hypocrisy, treat men as machinery, restrict their freedom by methods and terms, follow their own spirit, pervert right principles through selfishness and covetousness, turn the work from straightforward channels into crooked paths, dominate God's heritage, deny men their rights, and by deceptive reasoning grasp all they can without regard for their agreements or for the disappointment and wrong suffered by others.