2 CORINTHIANS 5:21
“For our sake he made him to be sin who knew no sin, so that in him we might become the righteousness of God.” This verse seems to present explicit testimony for a great exchange that took place on the cross: I give Christ my sin and he gives me his righteousness. Hear Wright’s interpretation:
The verse has traditionally been read as a somewhat detached statement of atonement theology: “we are sinners; God is righteous, but in Christ what Luther called a ‘wondrous exchange’ takes place, in which Christ takes our sin and we his ‘righteousness’.” … the difficulty ... is … there seems to be no good reason why [Paul] suddenly inserts this statement into a discussion whose thrust is quite different, namely, a consideration of the paradoxical apostolic ministry in which Christ is portrayed in and through the humiliating weakness of the apostle (4:7-6:13)…It seems that Wright’s interpretation “restricts the ‘we’ arbitrarily to Paul and his apostolic colleagues.” Additionally, it seems “more likely that the reference is to all believers, in view of the universal scope attributed to God’s reconciling activity in v. 19.” A parallel doctrine to imputation - substitutionary atonement - is presented in the plainest of terms in this verse.
Additionally, this text alludes to Old Testament sin offerings (cf. Isa. 53; Rom. 8:3); these carried with them the idea of substitution. This idea is front and center in the gospels as well, as Jesus was offered up as the sinless lamb (cf. John 1:29, 36).
Interpreting this passage in the Reformed vein has the added benefit of making sense of the rest of the passage, especially the shocking idea of Christ knowing and becoming sin:
…the statement God made him who had no sin to be sin is balanced by the opposite statement, so that in him we might become the righteousness of God. If becoming the righteousness of God means that God has pronounced judgment in our favor and put us in right relationship with himself, then to become sin, as the opposite of that, would mean that God had pronounced judgment against Christ (because he took upon himself the burden of our sins; cf. Is. 53:4–6, 12) with the result that his relationship with God was momentarily, but terribly beyond all human understanding, severed (cf. Mt. 27:46) for us.There is much more that Wright and others have said about this and indeed there is much more that could be said but for now I think one can see that Wright’s interpretation of 2 Corinthians 5:21 is unsustainable.
 See, for example, Robert H. Gundry, “TheNonimputation of Christ’s righteousness,” Justification:What’s at Stake in the Current Debates, ed. Mark Husbands and Daniel J.Treier (Downers Grove, IL: IVP, 2004) and “Why I Didn’t Endorse ‘The Gospel ofJesus Christ: An Evangelical Celebration?’ … even though I wasn’t asked to,” Books & Culture, vol. 7, no. 1,Jan-Feb 2001, 6.
 John Piper, Counted Righteous in Christ: ShouldWe Abandon the Imputation of Christ’s Righteousness? (Wheaton,IL: Crossway), 56.
 Piper, Counted Righteous, 58.
 Luther called it the “happy exchange”;others have called it the “sweet exchange”.
 N.T. Wright, On Becoming theRighteousness of God: 2 Corinthians 5:21. Originally published in PaulineTheology, Volume II, ed. D.M. Hay (Minneapolis: Augsburg Fortress, 1993),200-208.
 David P. Massey, An Exegetical Look at Second Corinthians5:21. Unpublished paper given to me by the author in the Spring of 2012 atPhoenix Seminary.
 Margaret E.Thrall, 2 Corinthians in InternationalCritical Commentary, Vol. 1 (Edinburgh: T&T Clark International, 1994),431.
 In fact, the phrase “for us” or “for our”in Greek can mean a term for substitution. Greek Grammarian Daniel B.Wallace has some ultra-technical input on the notion of substitution found inthe relevant Greek proposition in GreekGrammar Beyond the Basics, (Grand Rapids, MI: Zondervan, 1996), 383-389.
 Colin G. Kruse, NewBible Commentary : 21st Century Edition, ed. D. A. Carson (4th ed.; DownersGrove, IL: Inter-Varsity Press, 1994), 2 Co 5:11–7:4.