I think that Joe is on the right track with his second response to this thread.
To reiterate my first post indicates that there is a clear difference in the two and the Holy Spirit goes into great detail in explaining the difference.
Let's assume that the birthright is the pardoning and forgiveness of sin and inheritance is gaining the world. Notice that Jacobs life is given in greater detail than that of Isaac's and even rival's that of Abraham's story. God always goes into detail when a sinner confesses and repents. He shows us that He will faithfully receive sinners unto repentance.
Jacob did not deceive his brother and his brother saw his immediate need as life or death. Esau thought about what he was about to do and considered his birthright as a useless item if he starved to death. His immediate need was greater and he chose the "soup".
Now think on Jacob for a moment. He did not have Esau's confession on a legal document. He had only the word of his brother that the birthright would be his. No doubt he told his mother everything that had happened between him and Esau. Now as I imagine what had happened is this, Rebekah overheard the following conservation of Isaac and Esau.
Genesis 27:1-5
1And it came to pass, that when Isaac was old, and his eyes were dim, so that he could not see, he called Esau his eldest son, and said unto him, My son: and he said unto him, Behold, here am I.
2And he said, Behold now, I am old, I know not the day of my death:
3Now therefore take, I pray thee, thy weapons, thy quiver and thy bow, and go out to the field, and take me some venison;
4And make me savoury meat, such as I love, and bring it to me, that I may eat; that my soul may bless thee before I die.
5And Rebekah heard when Isaac spake to Esau his son. And Esau went to the field to hunt for venison, and to bring it.
In these time it would be customary for the whole family to be present for this blessing. So there is deception upon deception going on here. (Joe touched on something that plays into this double deception, Jacob could have freely gave Esau the "soup". After all he is Esau's brother and as brothers they should share and share alike. Eventually Jacob will see that this is what he should have done.) Esau, as close as he was to his daddy, would surely have told Isaac of his encounter with Jacob and Isaac would see that Esau gets the blessing. Rebekah hears the underhanded plot and plots to make sure that Jacob gets what has been sold to him.
When the deceptions are over Esau declares that he will kill his brother and Rebekah sends Jacob away with nothing but the clothes on his back for fear that Esau would make good on his threat.
What does Jacob have? Nothing but the word of a dying father that did not favor him in the first place. I can imagine Jacob as he went off to sleep resting his head upon that rock at bethel. The thought that must have been upon his heart. Who could he trust anymore? His mother was a deceiver, his brother was a lier and his daddy did not love him. I can even imagine that he did not like himself very well either. He was selfish, in that he would not share with his brother, and a deceiver as he capitulated to the deceptions of his mother.
It was at this time just as he had fallen fast asleep he saw the "ladder" that the angels used to go and come between Heaven and Earth. Then Jacob said this,
Genesis 28:16-22
16And Jacob awaked out of his sleep, and he said, Surely the LORD is in this place; and I knew it not.
17And he was afraid, and said, How dreadful is this place! this is none other but the house of God, and this is the gate of heaven.
18And Jacob rose up early in the morning, and took the stone that he had put for his pillows, and set it up for a pillar, and poured oil upon the top of it.
19And he called the name of that place Bethel: but the name of that city was called Luz at the first.
20And
Jacob vowed a vow, saying, If God will be with me, and will keep me in this way that I go, and will give me bread to eat, and raiment to put on,
21
So that I come again to my father’s house in peace; then shall the LORD be my God:
22And this stone, which I have set for a pillar, shall be God’s house: and of all that thou shalt give me
I will surely give the tenth unto thee.
His statement is that of an attitude of cynicism. However, there is this character of Jacob that no one ever mentions, he is true to his own word and when he commits to a goal he goes after it by any means possible. Later when he returns to this place he does just what he said he would do. He gets to Laban's and works 14 hard years for the woman he loves and is committed to her until the day he dies. In the meantime God is blessing his hard work and is increasing his blessings daily. By the time Jacob leaves Laban he leaves a very wealthy man.
He approaches Esau in great fear that Esau still harbors a grudge. Jacob offers a great portion of his wealth to Esau. He has finally learned to share. Esau is not angry and they hug each other while weeping. Esau's wealth is enormous and he thinks that he has not suffered any loss.
Jacob goes on to have two sons by his favored wife Rachel. Dying in childbirth to Benjamin, Jacob is understandably partial to these two sons. However he must learn another lesson. He should be mindful of each and every son.
The jealous nature of the 10 sons towards Joseph's favored status drives them to the brink of murder. Judah steps in and advocates selling him to Ishmaelites on their way to Egypt. Jacob is devestated upon hearing the news of their connived story.
Thirty years pass and the land is ravished by a prolonged drought that has reduced Jacob's family to going to Egypt to buy food. Finally Joseph is found and all is brought right between Joseph and his brothers.
While on his death bed in Egypt Jacob does something very different than all of his fathers. He blesses all of his sons and his two grandsons. He divides his blessing freely. Jacob has learned Grace.
Working hard got him no where. Grace caused him to pass in peace. He died in Egypt totally dependent on his sons. His sons end up as slaves but they have the blessings of Grace.
Our birthright is not what is worked for but what is freely given. God is faithful to do what is needed to be done and make it free to all that will trust Him to do it.
Esau got that what is worked for and was hated by God for it, though Esau and his sons dwelt in splendor they were lost to the blessings of God.
Grace is our birthright. Only the grace of God is going to give the new birth of eternal life. John Chapter 3 explains that in detail. However I will leave you with this.
Ephesians 2:4-9
4But God, who is rich in mercy, for his great love wherewith he loved us,
5Even when we were dead in sins, hath quickened us together with Christ, (by grace ye are saved
6And hath raised us up together, and made us sit together in heavenly places in Christ Jesus:
7That in the ages to come he might show the exceeding riches of his grace in his kindness toward us through Christ Jesus.
8For by grace are ye saved through faith; and that not of yourselves: it is the gift of God:
9Not of works, lest any man should boast.
Grace is indeed the birthright. Inheritance is the accumulated wealth of the previous generation's hard work.