Dear Joseph:

This story in found in Genesis 27:1-33.

The biblical principle that is the basis of the answer to your question is found in Romans 8:28 ~ "We know that in everything God works for good with those who love him, who are called according to his purpose."

God can bring glory out of our sins and mistakes. He can facilitate His will, His salvation plan, out of our sins and mistakes. In other words, if our sins and mistakes are lemons, God can make sweet lemonade from it.

That is what God did with Jacob. The ends never justify the means, but God took the deception of Jacob and his mother to further His salvation plan, which was to bring about his chosen people, to bring about His covenant with Abraham, through the lineage of Abraham, Isaac, and Jacob, by-passing Esau (the line of Ishmael, Isaac's half-brother, from who came the Arab people and later Islam, had already been by-passed). Had Jacob and his mother not conspired to deceive Isaac, God would have guaranteed the lineage in some other way. But, the sin of Jacob, since it presented itself, was used to facilitate that salvation plan.

The Navarre Bible commentary states:

Rebecca apparently acts out of human motives, impelled by her love for her favorite (younger) son (cf. 25:28). God will use this favoritism to guide events so that his plans for the two sons take effect (cf. 25:23). Holy Scripture does not justify Rebecca's action, but God draws great good from it: the promises made to Abraham pass, through Jacob, to the people of Israel, his descendants.

… Isaac reaffirms his blessing after he discovers he has been deceived (cf. 28:3-4).

God Bless,
Bro. Ignatius Mary