Genesis 27

We now see how Jacob finally obtained Esau's  blessing. It is a tale of deception and taking advantage of his father's poor eyesight, and also urged on by his mother.

Isaac fully intended the blessing to go to Esau, and sent Esau out hunting in preparation for the event. Rebekah was listening in and saw that action needed to be taken if Jacob was to receive the blessing, otherwise it would be too late. Jacob was to get some game and pretend to be his brother. This involved dressing up as a hairy man. Rebekah took responsibility for the deception upon herself.

Jacob carried out the deception, but Isaac was a little suspicious. First because of how quick Jacob had been (to which Jacob took God's name in vain, attributing his speed to God). Then Isaac detected a difference in the voice, but was fooled by the animals fur that Jacob was wearing. He even challenged Jacob directly, and Jacob lied. Isaac then gives the blessing to Jacob. It was essentially the promise that God had given to Abraham in Genesis 12.

Just after this Esau arrived back and the deception became apparent. Isaac was trembling with rage. Isaac gave Esau a blessing of sorts, but, not surprisingly, Esau held a grudge against Jacob and vowed to kill him. Rebekah makes sure that Jacob goes away to stay with Laban in order to keep him safe.

All in all this is not a very glorious episode. Esau is reaping the fruit of his willingness to give up his birthright (which is more or less identical to the blessing, both being to do with inheritance). Jacob and Rebekah are acting deceitfully, and Isaac is the victim of a fraud. Yet later on in the Bible there are several references to this being God's plan. If it wasn't for this we could simply put the whole matter down to human frailty and sinfulness, yet it still formed part of God's plan. We can understand why Esau did not deserve the blessing, but there is no way that Jacob did deserve it. Perhaps one lesson is that if we receive the blessing of God we should never presume that this makes us morally superior.