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Against my better judgment to continue in this series of posts, the absence of the article before world in 2 Cor 5:19 leaves us to contemplate the abstract significance of this word (read pp 206-290 in the chapters entitled The Article in Greek Grammar Beyond the Basics by Daniel Wallace for more information). It was “a world,” not “the world,” that God was reconciling to Himself. Thus, when Paul says "a world," he means "a world" (note the a world being reconciled was in the world).


A world that includes every person who ever lived or will live:

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Objective Justification in Our Mission Outreach: An Exegesis of 2 Corinthians 5:18-19 by David P. Kushe
ko/smon. With this word Paul clearly teaches that God's act of reconciliation covers the whole world. It applies to the whole world, to every person, whether he lived before Christ, or at the time of Christ, or any time since Christ, or in any of the time still remaining before Christ comes again. Thus everyone is included in this word regardless of whether he ever comes to faith or not.
This same truth is taught in the similar context of Colossians 1. There in verses 16 and 20 we read: "For by him all things were created: things in heaven and on earth, visible and invisible … and through him (God was pleased) to reconcile to himself all things (ta_ pa/nta), whether things on earth or things in heaven, by making peace through his blood, shed on the cross."
In this context it is also most important to note that ko/smon in verse 19 is parallel to h9ma=j in verse 18. Remember that verse 19 is an expansion or explanation of verse 18 (cf. w(j o3ti) and then it becomes apparent that Paul is indicating that our reconciliation as believers is assured by the fact that the world was reconciled.

e9autw~|. As in verse 18 this pronoun is added to stress that God did not reconcile the people of the world to one another, but rather reconciled the whole world as a group to himself.

mh\ logizo/menoj. This participle is in apposition to h]n katalla/sswn and thus explains God's Christ-worked-world-reconciliation as merely a matter of accounting. Every individual in the world sinned and thereby incurred an unpayable amount on his account before God. Here Paul refers to the truth that while Christ was on earth he lived a perfect life which God put on the account of all men and he died as the substitute for all which God also credited to the account of all (cf. v 14b). Since by this perfect life and death Christ "blotted out the handwriting of ordinances which was against us" (Col 2:14), God no longer imputed anyone's sins to him; they were imputed to Christ. In verse 21 this truth is described in this way that "God made him who had no sin to be sin for us so that in him we might become the righteousness of God." It is important to note that this appositional mh\ logizo/menoj makes God's act of reconciliation basically one of negative accounting (i.e., not imputing, or not charging) rather than some kind of inner change in God or in man. God never changed in either his love or his justice; he loved man e0n xristw|~, and e0n xristw~| the justice which God's holiness required as the punishment for sin was satisfied completely. The spiritual change in man is worked, as Paul said in verse 17, only after he is "in Christ" and thus becomes a totally "new creation" who despises sin and loves God's good and gracious will. The only change which took place as a result of God's Christ-worked-world-reconciliation was in every sinner's account before God.

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Reconciling in 2 Cor 5:19 is a present tense participle revealing God continues to reconcile people to himself. Thus, reconciling the world takes place in and through Christ as a continuing activity. “Not reckoning unto them their trespasses,” is also a present tense of the participle, which indicates that God continues to release believers from their guilt.


Your interpretation of the text is untenable:

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A Note on Qe/menov in 2 Corinthians 5:19 by Dr. Siegbert W. Becker
If we interpret qe/menov as a circumstantial participle, as opponents of universal justification do, then whatever temporal significance this past participle has must be determined by the tense of the principal verb. It would then refer to an action which precedes the time indicated by h]n. It would in that case have to mean that after God had committed to Paul and the other apostles the word of reconciliation, he was, or existed, in Christ. In other words, Paul would be saying that the commissioning of the apostles antedates the incarnarion. But biblical history clearly demonstrates that the great commission was given after the resurrection and is in reality based on it (Lk 24:46f).
It is sometimes argued that since katalla&sswn is a present participle and qe/menov is an aorist, the commissioning of Paul must precede the reconciling, and for that reason the reconciliation spoken of here is one that takes place when the word of reconciliation is preached and men come to faith. This is absolutely untenable, since the temporal significance of a participle is determined first of all by the tense of the main verb and not by the tense of the other participles in the sentence.
We are therefore forced to interpret h]n…qe/menov as periphrastic. Paul used an aorist rather than a present participle because a present participle with h]n yields an imperfect tense. Such an imperfect tense (as in h]n…katalla&sswn) correctly portrays God's work of reconciling, since that was an ongoing work which began with the incarnation and ended with the resurrection. An imperfect tense, however, could hardly be used to describe the commissioning of Paul, which took place at a very definite and limited time when Paul was called to carry the gospel to the Gentiles. Therefore only an aorist construction serves to express what actually happened.