All this is from God, who through Christ reconciled us to himself and gave us the ministry of reconciliation; that is, in Christ God was reconciling the world to himself, not counting their trespasses against them, and entrusting to us the message of reconciliation. Therefore, we are ambassadors for Christ, God making his appeal through us. We implore you on behalf of Christ, be reconciled to God. (2 Cor. 5:18-20)
As Christians, we are called to be ambassadors for Christ; to represent our King as His messenger to proclaim His Word. In the secular world, ambassadors represent not themselves or their interests but the interests of their respective countries. Even if they personally feel a certain way, they do not express their personal feelings (or at least aren't supposed to do so), but only such as benefits their countries' interests.
The Christian is an ambassador for Christ, and thus represent Christ to his fellow men. This of course has many implications for our behavior, including how we live our lives and our witness for Christ to those who do not know Him. We will however focus on the aspect that is at contention here in the New Calvinism: The focus on being an ambassador in our attitudes in Gospel and Truth proclamation.
An organization that has became the de facto flagship of the New Calvinism, The Gospel Coalition Network, epitomized the mood of the New Calvinism in its handling of the truth, an improvement over the older New Evangelicalism half a century ago which jettisoned the importance of truth in her outreach. Instead of the perceived opposites found within "Fundamentalism" and the Postmodern Emerging Conversation, the Gospel Coalition has came up with a "mood" or approach to truth which they call a "chastened correspondence theory of truth", as stated
We adopt a “chastened” correspondence–theory of truth that is less triumphalistic than that of some in the older evangelicalism. But we also reject a view of truth that sees truth as nothing more than the internally coherent language of a particular faith– community. So we maintain, with what we hope is appropriate humility, the principle of sola Scriptura. (I.4.1) 
The older evangelicalism is considered "more triumphalistic" with its uncompromising proclamation of the Truth which is perceived to not take into account the fact that we perceive the Truth only partially and infallibly. Since our perception tints our view of the Truth (perspectivism), we are to be humble in our proclamation of the truth as we may be wrong. Such humility or a chastened attitude precludes the prophetic proclamation of Truth as being definitely THE truth, unless it be accompanied by disclaimers that we may be wrong and therefore invite others to correct us if they are able to; to show us that our perception may not be totally true. So says the New Calvinism and the Gospel-centered movement. However, is this view of ourselves and our knowledge of truth biblical?
First of all, it must be conceded that we are most definitely not neutral with regards to Truth, and therefore we may not be definitely true. Sometimes even what we strongly think is true may be wrong, and we should welcome criticism and evaluate our theories accordingly. However, to extrapolate this fact "We are not always definitely true" to "We are always not definitely true" is a logical fallacy, a fallacy hat the Gospel-centered movement and New Calvinism are in fact committing.
How do we Christians come to know biblical truth? We know biblical truth through God's revelation in the Scriptures, which are objective and absolute truths free from all human perspectives. The Truth therefore is present with us, and this truth being free from human perspectives and biasness will never be wrong and needs no apologizing. After all, this is what is meant when we say that Scripture is the ultimate authority for all of life.
The next step has to do with internalizing the external Truth into our minds, which of course is not an infallible process due to sin. In point of fact, the unregenerate cannot receive the truth of Christ, and are not able to perceive them as truth but only as seeming folly (1 Cor. 2:14). However, the same passage informs us Christians that we can and do definitely understand God's Truth. As it is written:
Now we have received not the spirit of the world, but the Spirit who is from God, that we might understand the things freely given us by God. ... The spiritual person judges all things, but is himself to be judged by no one. “For who has understood the mind of the Lord so as to instruct him?” But we have the mind of Christ. (1 Cor. 2:12, 15-16)
Those who are truly believers, the regenerate, will have the mind of Christ and the Holy Spirit (cf Jn. 16:13; 17:17) and understand God's truth. No doubt new believers have to grow in Christ and renew their mind (Rom. 12:2), but definite knowledge of the truth can be achieved, otherwise the passage in 1 Cor. 2 makes absolutely no sense, giving us the contradiction that even with the mind of Christ and being able to judge all things, the truths we obtained through having the mind of Christ are not necessarily true. We must here differentiate between definite and exhaustive knowledge of the truth: Definite knowledge of truth deals with the quality of our knowledge of the truth as being 100% confident to be true, while exhaustive knowledge of truth deals with the quantity or depth of our knowledge of the truth. We most definitely cannot obtain exhaustive truth since we are finite and God is infinite, but there is nothing to prohibit the definite acquisition of truth especially since we have the mind of Christ.
All of this ties back in to the issue of being an ambassador for Christ. Ambassadors are to represent their countries, not themselves. Similarly, in Gospel and truth proclamations, we represent God and not ourselves. We are still not perfect and are still sinful, but we are NOT representing our own human frailties but the perfect, infallible and sinless God whose greatness surpasses our puny human frames. Having given the mind of Christ, and thus able to definitely know truth, are we then to shrink back and adopt a "chastened" attitude with regards to truth? We are jars of clay containing the truth of Christ (2 Cor. 4:7). Is the value of the treasure fundamentally affected by the type of jar it is in? So why are we so focused on ourselves rather than the Christ who uses us weaklings to proclaim His truth?
We are therefore to be bold in our proclamation, because the message we have does not depend on the state of the vessel for its existence and truthfulness. Our job is in presenting it clearly through faithful exegesis of Scripture, and thus let the Scriptures speak for themselves, and we need not ever apologize or try to be humble in its proclamation. In fact, since this is God's truth we are talking about, humility is portrayed in proclaiming it authoritatively, and the "chastened" attitude is in fact false humility which devalues the Word of God by making its proclamation less authoritative than what it actually is.
Will the New Calvinists reject this new "chastened" attitude towards the Truth of Scripture? Will we rather let Scripture and Scripture alone dictate to us the relative definiteness of the various truths of Scripture, and react accordingly, instead of allowing philosophical and cultural analyses to shape our epistemology?
We have seen five major issues of concern with New [Evangelical] Calvinism. All of these are serious in their own right and have the potential to derail the entire movement from the Scriptures. On top of this, the issue of pragmatism (part of New Evangelicalism) has lately reared its ugly head, seen especially when it comes to defending Driscoll and Keller from criticism by pointing to how successful they have been in reaching the lost and church planting. Now each one is a serious concern in its own right, but compounding them all together and it seems that the New Calvinism is fraught with many problems as they continue in the errors of their predecessor the conservative wing of New Evangelicalism. Will we and the New Calvinists be willing to listen to Scripture and be willing to biblically re-evaluate New Evangelicalism, or will we continue in the deluded thinking that as long as our doctrine and our Gospel narrowly defined is orthodox, our larger worldview and ministry philosophy are irrelevant? Will we learn from Scripture and from history, or will we repeat the same mistakes over again?
Those who cannot remember the past are condemned to repeat it. - George Santayana
May God be with us and open our eyes to see the truth and rejects the errors in the New Evangelical Calvinism. Amen.
 Theological Vision for Ministry, The Gospel Coalition Network (http://www.thegospelcoalition.org/about/foundation-documents/vision)
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