Ellen Davis has a great essay in a collection entitled The Whirlwind, ed. by Stephen Cook, et al.
She recognizes the textual parallels in the characters of Job and Jacob and specifically notices the description of both men as tam or “blameless”. Davis suggests, following the Targum’s rendering of Gen. 25:27 that this “integrity” is a sort teachability. Specifically, she suggests that it is a kind of obsession with the blessing of God. She traces Jacob’s life from tricking his brother into giving him the birthright, stealing it and deceiving his father, and struggling with his father in-law for the blessing of a wife, he finally comes face to face with God, wrestling with Him and refusing to let go until he receives a blessing.
Davis applies this connection to Job and then based on her dating of the book suggests its applicability to post-exilic Israel, a nation still struggling, wrestling and the author hopes still obsessed with seeking the blessing of their God. Whether the dating is right or not, the application seems right.
On this reading, to be “blameless” is not in the first place a moral designation. It is rather the calling to seek the blessing of God, to search for God Himself, until He is found. Jacob finally sees God face to face, Moses speaks to God face to face like a friend, and Job eventually meets God and sees Him with His eyes.
These brief allusions all point to the ultimate “blameless” One, Jesus Christ, who is likewise obsessed with the blessing of God His Father. And this Jesus ultimately ascends to the Father and pours out the Spirit upon His people, blowing this calling wide open to all of God’s people. All of God’s people are called to be sons, called and re-created with capacities for obsession with the blessing of God.