Is the Doctrine of Justification Optional To Believe?

Which is biblically right....

This:

The gospel we present has eternal consequences. If it is the true gospel, it can direct men and women into the everlasting kingdom. If it is a corrupted message, it can give unsaved people false hope while consigning them to eternal damnation. This is not a trivial matter for theologians to speculate on. It is an issue every lay person must understand and get right. 

~ John MacArthur

or this:

The reason for saying, “when consistently worked out,” is because I think it is possible to inconsistently deny the truth of imputation while embracing other aspects of the gospel (blood bought forgiveness, and propitiation, for example), through which God mercifully saves.

I am thankful that God is willing to save us even when our grasp of the gospel may be partial or defective. None of us has a comprehensive or perfect grasp of it.

~ John Piper  (This was a clarification of his tweet on praying for a new pope.)

One of them is completely wrong and it's not John MacArthur. 

2Co 5:20  Therefore, we are ambassadors for Christ, as though God were making an appeal through us; we beg you on behalf of Christ, be reconciled to God. 

2Co 5:21  He made Him who knew no sin to be sin on our behalf, so that we might become the righteousness of God in Him. 

Rom 5:18  So then as through one transgression there resulted condemnation to all men, even so through one act of righteousness there resulted justification of life to all men. 19  For as through the one man's disobedience the many were made sinners, even so through the obedience of the One the many will be made righteous. 

John MacArthur also stated in part in "Jesus' Perspective of Sola Fide" :

Many who have embraced "the New Perspective on Paul" are also proposing a different slant on the doctrine of justification by faith. When the text of Scripture is interpreted in the new light, they say, Pauline support for the principle of sola fide, the doctrine of imputation, and the distinction between law and gospel doesn't seem quite so strong.

We say that's nonsense. We reject the historical and hermeneutical revisionism of the New Perspective, but regardless of how one interprets the apostle Paul, it is quite clear that Jesus taught justification by faith alone. To abandon this truth is to abandon biblical soteriology altogether.

No doctrine is more important to evangelical theology than the doctrine of justification by faith alone--the Reformation principle of sola fide. Martin Luther rightly said that the church stands or falls on this one doctrine.

Historic evangelicalism has therefore always treated justification by faith as a central biblical distinctive--if not the single most important doctrine to get right. This is the doctrine that makes authentic Christianity distinct from every other religion. Christianity is the religion of divine accomplishment--with the emphasis always on Christ's finished work. All others are religions of human achievement. They become preoccupied, inevitably, with the sinner's own efforts to be holy. Abandon the doctrine of justification by faith and you cannot honestly claim to be evangelical.

In other words, those who trust Jesus Christ for justification by faith alone receive a perfect righteousness that is reckoned to them. Those who attempt to establish their own righteousness or mix faith with works only receive the terrible wage that is due all who fall short of perfection. So the individual as well as the church stands or falls with the principle of sola fide. Israel's apostasy was rooted in their abandonment of justification by faith alone: "For not knowing about God's righteousness, and seeking to establish their own, they did not subject themselves to the righteousness of God" (Rom. 10:3).

What must we do to be saved? The apostle Paul answered that question for the Philippian jailer in the clearest possible terms: "Believe in the Lord Jesus, and you shall be saved" (Acts 16:31).

Paul's key doctrinal epistles--especially Romans and Galatians--then expand on that answer, unfolding the doctrine of justification by faith to show how we are justified by faith alone apart from human works of any kind.

At least, that is the historic evangelical interpretation of Paul. But that's the very thing under attack by the New Perspective.

The tax-gatherer was justified. God declared him righteous, imputing to him the full and perfect righteousness of Christ, forgiving him of all unrighteousness, and delivering him from all condemnation. Forever thereafter he stood before God on the ground of a perfect righteousness that had been reckoned to his account.

That is what justification means. It is the only true gospel. All other points of theology emanate from it.

End quote.

See the entire article here.

Because Federal Visionism/ New Perspective on Paul is acceptable to Piper,  it may account for his tossing it aside as unnecessary to believe. Go here for a treatment on Piper's view of Justification/Federal Visionism (note: I don't accept Robbin's Convenantalism, but he's right on the rest in his critique on Piper). Also note that Piper has had Federal Visionism proponent Doug Wilson at repeated conferences, last year at the  Conference  For Pastors, being the most recent.

What is Justification? As John MacArthur notes:In its theological sense, justification is a forensic, or purely legal, term. It describes what God declares about the believer, not what He does to change the believer. In fact, justification effects no actual change whatsoever in the sinner's nature or character. Justification is a divine judicial edict. It changes our status only, but it carries ramifications that guarantee other changes will follow. Forensic decrees like this are fairly common in everyday life.

In biblical terms, justification is a divine verdict of "not guilty — fully righteous." It is the reversal of God's attitude toward the sinner. Whereas He formerly condemned, He now vindicates. Although the sinner once lived under God's wrath, as a believer he or she is now under God's blessing.

Justification is more than simple pardon; pardon alone would still leave the sinner without merit before God. So when God justifies He imputes divine righteousness to the sinner (Romans 4:22-25). Christ's own infinite merit thus becomes the ground on which the believer stands before God (Romans 5:19; 1 Corinthians 1:30; Philippians 3:9). So justification elevates the believer to a realm of full acceptance and divine privilege in Jesus Christ.

Therefore, because of justification, believers not only are perfectly free from any charge of guilt (Romans 8:33) but also have the full merit of Christ reckoned to their personal account (Romans 5:17). Here are the forensic realities that flow out of justification:

- We are adopted as sons and daughters (Romans 8:15)
- We become fellow-heirs with Christ (v. 17)
- We are united with Christ so that we become one with Him (1 Corinthians 6:17)
- We are henceforth "in Christ" (Galatians 3:27) and He in us (Colossians 1:27)

End quote.

Source: The Gospel According to the Apostles, by John MacArthur

John Piper is saying all of this about Justification can be rejected and still be saved. He couldn't be more wrong.