Matthew 6:33 reads, “But seek ye first the kingdom of God and His righteousness, and all these things will be added to you.” (ζητεῖτε δὲ πρῶτον τὴν βασιλείαν [τοῦ θεοῦ] καὶ τὴν δικαιοσύνην αὐτοῦ, καὶ ταῦτα πάντα προστεθήσεται ὑμῖν.)
This is sometimes understood by certain evangelicals as meaning “Seek ye first the kingdom of God and the imputation of Christ’s righteousness to you.”
But it does not.
“The kingdom of God and His righteousness” is a hendiadys. N.T. Wright is correct about what “the righteousness of God” means in 2 Cor. 5:21 (“God made Him who knew no sin to become sin for us, that in Him we might become the righteousness of God.”). He says (in this paper):
Paul’s contention, supremely in Romans, is that in Christ Israel’s God has indeed been faithful to the covenant made with Abraham, but precisely not in the nationalistic way which Israel imagined… [2 Cor. 5:21] is not a parenthetical statement of individual soteriology… It is a climactic statement of the whole argument so far. The “earthen vessel” that Paul knows himself to be (4:7) has found the problem of his own earthiness dealt with, and has found itself filled, paradoxically, with treasure indeed: “for our sake God made Christ, who did not know sin, to be a sin-offering for us, so that in him we might become God’s covenant-faithfulness.” The “righteousness of God” in this verse is not a human status in virtue of which the one who has “become” it stands righteous” before God, as in Lutheran soteriology. It is the covenant faithfulness of the one true God, now active through the paradoxical Christ-shaped ministry of Paul, reaching out with the offer of reconciliation to all who hear his bold preaching.
If we go along with Wright and see “the righteousness of God” as a technical term for His faithfulness to His covenant, especially His covenant with Abraham, then Jesus’ exhortation in Mt. 6:33 becomes readily understandable as a hendiadys, for the coming of the Kingdom is precisely the “righteousness of God” which Simeon, Anna, Peter, Andrew, and all the faithful Jews of Jesus’ day were eagerly awaiting.