Jacob and Esau grew to be men. They were of opposite personality and character.
"Once when Jacob was cooking some stew, Esau came in from the open country, famished. Esau said to Jacob, "I'm starved! Give me some of that red stew!"
"All right," Jacob replied, "but trade me your rights as the firstborn son."
"Look, I am about to die," Esau said. "What good is the birthright to me?"
So, he sold his rights to Jacob as firstborn.
Genesis 25:29-34
Matthew Henry's Concise Commentary
25:29-34 We have here the bargain made between Jacob and Esau about the right, which was Esau's by birth, but Jacob's by promise. It was for a spiritual privilege; and we see Jacob's desire of the birth-right, but he sought to obtain it by crooked courses, not like his character as a plain man. He was right, that he coveted earnestly the best gifts; he was wrong, that he took advantage of his brother's need.
The Bible says, "So Esau despised his birthright."
Their father Isaac ( probably not knowing about his son's transaction) felt he was going to die soon, so he called Esau to him and said, "Prepare me the kind of tasty food I like and bring it to me to eat, so that I may give you my blessing before I die."
His mother Rebekah, overheard the conversation and told Jacob she would cook the food and that Jacob should go in to Isaac pretending he was Esau so that he would receive the blessing instead of his brother. And although Jacob argued with her, he finally gave in and lied to his father to take the blessings from Esau.
"Isaac trembled exceedingly - Those that follow the choice of their own affections rather than the dictates of the Divine will, involve themselves in such perplexities as these. But he soon recovers himself, and ratifies the blessing he had given to Jacob, I have blessed him, and he shall be blessed - He might have recalled it, but now at last he is sensible he was in an error when he designed it for Esau. Either recollecting the Divine oracle, or having found himself more than ordinarily filled with the Holy Ghost when he gave the blessing to Jacob, he perceived that God did as it were say Amen to it."
"Esau held a grudge against Jacob because of the blessing his father had given him. He said to himself, "The days of mourning for my father are near; then I will kill my brother Jacob." Genesis 27:41
God had told Rebekah that Esau would serve Jacob. Isaac chose to ignore this and wanted Esau to be the head of the family. Rebekah resorted to lies to make Jacob the head. Jacob had thought he could take advantage of Esau's hunger and buy the blessing.
None of them trusted in God about this. None of them waited for God's will to be done in His own way. Rebekah paid for this by never seeing her beloved son Jacob again. Jacob paid by having to run away from the murderous anger of Esau. It is never a good idea to try to make good things happen in an unrighteous way.
