Jacob, the youngest by only a few seconds, was born holding the heel of his “older” brother Esau. It appeared at birth Jacob always wanted the birthright that came with being the firstborn. The birthright put the oldest in the position of inheritance, the one that would carry on the family name and business. However, a prophecy had been spoken about these two before they were born:
LORD said to her, “Two nations are in your womb, and two peoples from within you will be separated; one people will be stronger than the other, and the older will serve the younger. “ Genesis 25:23
God knew these two would always be at odds. He also knew the older would serve the younger—a strange statement since the younger always served the older. So when the father Isaac was old, it came time for him to bless his twin sons. Jacob, ever the deceiver, worked with his mom to trick his dad into thinking he was Esau and received the blessing, which in those days was a big deal. Without legal documents or lawyers, verbal blessings were the binding contracts between people. By blessing Jacob, Isaac, though deceived, made a vow and a promise to Isaac, instating him as the firstborn.
The term firstborn usually meant the first born, however, it pointed more to the position of prominence or importance of the firstborn. Isaac gave Jacob the family business and family inheritance.
My opinion is Jacob was a deceiver, an underhanded, selfish mommy’s boy who wanted his own way and manipulated others to get what he wanted. He’s no hero. However, he got a taste of his own medicine when Laban tricked him into marrying both of his sisters and his own boys deceived him into thinking Joseph was dead. God didn’t let Jacob off the hook that easily without learning his lesson.
In retrospect, Jacob was the right person to carry the line of Abraham and Isaac. The choices he made were more in line for God’s will. Esau became a warrior and married the wrong women.
Also, technically, Jacob did share in the firstborn status. He was born holding the heel of Esau. If ever there was a double birth, this is it. Entering the world just seconds behind a brother hardly matter.
Jesus’ family line is full of liars, cheats and prostitutes. They aren’t perfect. Only Jesus was perfect, but He came to show that it didn’t matter what your family line looked like, you could overcome their hereditary sin and not make the same mistakes.