For decades, he's sported the quintessential Christian man persona. Leading his family in home Bible studies, evangelizing unbelievers, ensuring books by authors like Tozer are constantly on his nightstand and faithful church service have characterized his life.
But just recently, it's come to light that during all this time he's participated in gross, hidden and consistent sinful behavior and life-destroying addictions. He now wants nothing to do with Christianity.
During this same period, she taught teen Bible studies at church, constantly listened to Christian music, and encouraged other women to follow Christ. Yet, she also has led a double life hidden from her husband and family and is now living with another man. Amazingly, she told us recently that she thinks she is doing a good thing for the man she is now living with and believes she is positively influencing him in a spiritual way.
These two friends of my family give me much pause and force me to think long and hard about true saving faith. Yes, the Apostle Paul makes no bones about the fact that in this life we will always struggle with sin (Rom. 7:14-25), but yet Scripture also makes it clear that there are those who enter the Christian faith and depart (Matt. 13:1-23) and others who believe they are true believers but are not (Matt. 7:15-23).
The Bible tells all of us to conduct a spiritual exam of ourselves to ensure we're truly born again. Paul says, "Test yourselves to see if you are in the faith; examine yourselves! Or do you not recognize this about yourselves, that Jesus Christ is in you — unless indeed you fail the test?" (2 Cor. 13:5). Like Paul, Peter says: "Therefore, brethren, be all the more diligent to make certain about His calling and choosing you" (2 Pet. 1:10).
How does one "make certain" they are really saved and what kind of "test" is Paul talking about? Put another way, how do you clearly differentiate between a Christian who struggles with sin and someone who is no true Christian at all, especially when the person in question is you
The Most Important Question in Christianity?
During the Great Awakening, Jonathan Edwards was challenged as to the authenticity of the faith being proclaimed among the New England converts. In response to his critics, Edwards wrote his Treatise Concerning Religious Affections
, which may be the most thorough work ever done on the subject of what constitutes true saving faith.
Edwards begins his book with what well may be the most important question ever asked: "There is no question whatsoever, that is of greater importance to mankind, and what is more concerns every individual person to be well resolved in, than this: What are the distinguishing qualifications of those that are in favor with God, and entitled to his eternal rewards?"
In typical Edwards' style, the brilliant theologian leaves no stone unturned in addressing the question. His answer, in summary, is this: the principle evidence of life is motion (we live, move, breathe, etc.), and transferring that law to the spiritual realm, Edwards says that, "Holy practice [or motion] is the proper evidence of saving faith." 
Such a simple statement, yet one that causes much turmoil when put forward in the Church today.
"You're Teaching Works Salvation!"
The first time I taught through a series on how to perform a spiritual self-exam to ensure one is really saved, a guy in the class strongly objected to my claim that the primary way to separate the wheat from the tares is to utilize Edward's uncomplicated principle. "You're teaching works salvation!" he charged.
When I asked him how a person could know that they were a true Christian, he cited Romans 10:9-10 and said all someone needs to do is confess Jesus as Lord and that was it. "So you're saying that you can live any way you choose — commit continuous sin such as adultery — and that no change in life is required?" At that question, he sputtered like a car trying to start, primarily I think because his wife was sitting right beside him and may not have liked the way he really wanted to answer.
However, the idea that holy motion toward the things of God indicates saving faith is not works salvation at all. Rather it highlights an important distinction: there is a difference in the efficient cause of salvation and the evidences of that salvation.
Neither Edwards nor I believe works saves anyone; Scripture makes it clear that such is not the case (e.g. Eph. 2:8-9). We are saved solely by the sacrifice of Christ and His atoning death for us.
But the Bible is equally plain that easy believism — one that omits repentance and holy fruit that emerges from a tree that has had life restored to it — is out of step with Heaven's economy.
With All Due Respect to Luther
Martin Luther may have viewed the book of James with skepticism, but I don't think there's any clearer discourse on the subject of false vs. saving faith in the New Testament. In the second chapter of James, the apostle asks a question that sums up his position on the matter: "What use is it, my brethren, if someone says he has faith but he has no works? Can that faith save him?" (James 2:14).
It's fairly obvious what answer the apostle expects.
In vv. 14-16, James (like Edwards) makes his case for "holy practice" being the chief evidence of saving faith and concludes his remarks in the same way I've summarized Edward's position: "For just as the body without the spirit is dead, so also faith without works is dead" (James 2:26).
This truth is everywhere is Scripture. Whether it's John the Baptist and Jesus teaching on the differences in the fruit of good vs. bad trees (Matt. 3:10, 7:16, 12:33; Luke 6:44, 13:7; John 15:2, 6), Christ's parables of the ten virgins (Matt. 25:1-13), the sower (Matt. 13:3-9, 18-23), and the wheat/tares (Matt. 13:24-30, 36-43), Paul's talk of those who deny God by their deeds (Titus 1:16), or the writer of Hebrews' illustration of ground that brings forth a good crop vs. thorns (Heb. 6:7-8), the Bible's statement of a new creation in God producing good works that signifies real salvation is hard to miss.
Bookending the Salvation Experience
In his penetrating book The Atonement
, the English Congregationalist leader R. W. Dale rightly bookends the saving faith experience when he says, "Evangelical preachers have never hesitated to maintain the absolute necessity of repentance as an antecedent of faith; they should not hesitate to maintain the absolute necessity of good works as a consequent of faith." 
While there is no way to improve on Dale's statement, we are left with the question: what type of good works are we talking about? After all, the people discussed at the outset of this article exhibited many different Christian 'works'. The Pharisees appeared to be the role models of Judaism and yet Jesus asked them, "How will you escape the sentence of Hell?" (Matt. 23:33).
Let us understand that simple belief in God is not enough because, as James says, "the demons also believe and shudder" (James 2:19).
We get glimpses of the answer in Jesus' stinging rebuke against the Pharisees where He tells them how they "are like whitewashed tombs which on the outside appear beautiful, but inside they are full of dead men's bones and all uncleanness" and that they have "neglected the weightier provisions of the law: justice and mercy and faithfulness" (Matthew 23:27, 23).
The fact is, one day the tare grows up and showcases what it really is. While some may appear Christian on the outside, sooner or later, they become living and breathing examples of what Peter bluntly describes: "The dog returns to its own vomit, and the sow, after washing herself, returns to wallow in the mire." (2 Pet. 2:22). Their "affections" (as Edwards terms it) have not been changed nor are permanent with respect to God.
It's my hope and prayer that after you self-administer the test of Scripture where saving faith is concerned, you don't find yourself in the situation Peter describes, but rather pass the test with flying colors. If, by some chance, you don't, then please seek God in prayer, repent of your past, call on the name of Christ, be born again, and walk in the power of the Spirit from this day forward.
1. Jonathan Edwards, A Treatise Concerning Religious Affections, Kindle Edition, pg. 1, my emphasis.
2. Edwards, pg. 298.
3. R. W. Dale, The Atonement, Kindle Edition, Loc. 1770.