As it is written - Malachi 1:2-3. That is, the distribution of favors is on the principle advanced by the prophet, and is in accordance with the declaration that God had in fact loved the one and hated the other.
Jacob - This refers, doubtless, to the posterity of Jacob.
Have I loved - I have shown affection for that people; I have bestowed on them great privileges and blessings, as proofs of attachment. I have preferred Jacob to Esau.
Esau - The descendants of Esau, the Edomites; see Malachi 1:4.
Have I hated - This does not mean any positive hatred; but that he had preferred Jacob, and had withheld from Esau those privileges and blessings which he had conferred on the posterity of Jacob. This is explained in Malachi 1:3," And I hated Esau, and laid his mountains and heritage waste for the dragons of the wilderness;" compare Jeremiah 49:17-18; Ezekiel 35:6. It was common among the Hebrews to use the terms "love" and "hatred" in this comparative sense, where the former implied strong positive attachment, and the latter, not positive hatred, but merely a less love, or the withholding of the expressions of affection; compare Genesis 29:30-31; Proverbs 13:24, "He that spareth his rod hateth his son; but he that loveth him chasteneth him betimes;" Matthew 6:24, "No man can serve two masters, for either he will hate the one and love the other," etc.; Luke 14:26, "if any man come to me, and hate not his father and mother, etc." -Barnes comentary.
During the OT God did choose a nation over all other nations. God chose a lineage of people to bring about the Savior of the WORLD.
God acted in ways to bring history to a point history was finally ready for the prophecies of a savior to be made real.
God preferred Jacob over Esau. Both knew of God and surely was taught of God. But one lived worldly and one found himself wrestling with God and living for God.
God knew these two children would end up that way. Just as he knows who will be left in the book of life. Just as he knew Judas would betray Jesus.
He is all knowing and knew Esau would not choose God. He knew Judas would betray. God didnt force them he knew.
He hardened pharoahs heart. Just as Saul was allowed to be tempted by evil Spirits, so was Pharaoh. And they without force gave in by their own desires to do evil. Reprobate mind.
Just as Job in the first few verses of God speaking to Job says who are you to question me?
Its unthinkable to try and explain what Gods activities are compared to human free will. We are told a lot of Gods activities in the OT to bring about Gods promise.
Gods promise to bring a savior to save the world. It was Gods plan all along knowing Adam due to free will would give birth to sin.
We are living in the promise. The grace by faith. God has now gave the world a choice. At what extent is Gods activities to bring forth the end. We are given signs but do we know if Gods hand is active in bringing the end, or if God can see in future human events when its time for him to come.
We seem to get confused with OT actions of God was to bring a savior in NT to save ALL who believes.
We become the elect once we answered the calling of God in faith.
Almost the whole world has had Gods Word preached. Will they chose to answer the call within to believe in Christ or remain in rebellion.
Thank God everyone has this choice but sadly many ignore the tugging of God on ones soul.