Justification is the article by which the church stands or falls.
~attributed to Martin Luther
Christian theological discussions and debates quite often boil down to this: The doctrine of salvation by grace alone through faith alone (aka “justification by faith”). Unfortunately, many such dialogues produce more heat than light (thus evidencing that we are certainly saved by grace alone).
To illustrate: How are the following sentiments helpful?
Is Arminianism a damnable heresy? Yes. . . . Are pastors who teach Arminianism damnable heretics who are not Christians and who will certainly go to hell? Ultimately, this is up to God to decide . . . It would seem to be very difficult, if not impossible, to be trusting in Jesus Christ alone if you hold to [Arminian doctrine]. 
The false Gospel of the TULIP turns the Good News of Christ into a bad news. . . . The TULIP gospel does not say that God loved the world. So it is a false gospel. . . . The TULIP gospel which comes to you in the form of ‘Doctrines of Grace’ is indeed a very ungracious Gospel . . . the TULIP gospel of calvinism [sic] is a false gospel. 
Should we automatically anathematize those who understand the doctrine of justification by faith somewhat differently from us? I don’t think we should—not if we truly believe the doctrine.
(For those whose heads remain unexploded, let me explain.)
There is a difference between the doctrine of justification by faith alone and being justified by faith alone. But I fear we commonly fail to make this distinction. As soon as we begin to interject our “yeah buts” into the conversation, we are in danger of conflating the two.
Yeah…he says he believes in Jesus BUT he denies free-will…his “god” is the devil of Calvinism.
Yeah…she says she’s saved by grace alone BUT she thinks her faith preceded her “regeneration.”
Consider. Is repentance from sin and trust in the Christ of scripture—that He was the divine, sinless Son of God incarnate who died for sinners and rose again from the dead—sufficient to save?
Are we in fact saved by faith alone?
Please understand this is not a call to a minimalist view of faith. Nor is it my intention to downplay the importance of doctrine or to compromise theological distinctives. I am simply contending that if we are indeed justified by faith alone, we should not damn those who repent of sins and believe in Jesus Christ as their only Lord and Savior on the sole basis of doctrinal disagreement or imprecision.
It’s not doctrine alone, but faith alone.