A friend asked me: "If there is an initial justification; if upon receiving Jesus we have passed from death to life, is the final justification receiving what has been ours all along? Or is it something that can be lost or forfeited, so a person was justified in God's sight on one day, but because of sin later, they are going to be condemned on the final judgment day? If that is so, When did God uncancel the debt and take it from the cross? (Colossians 2:14) . Also if the first justification can be lost or forfeited, why does John have no doubt that those who went out from us were NEVER of us? (1 John 2:19).
My wife likes to tell me that the spiritual gift I should practice and emphasize in my life and writing is the ability to deal honestly with what Scripture says. I can tell you from experience that dealing honestly with Scripture, setting aside tradition and what you are sure you know, is a furiously difficult thing to do. When discoveries are made, the work seems well worth it. At other times, especially when I find out I have seriously misunderstood a Scripture or a subject and have to tell some jerk that he was right, being honest with Scripture is extremely painful.
My answer to my friend was more of the joyous discovery kind of feeling. My general process is to examine the Scriptures referenced in the questions openly and honestly while, initially, ignoring the argument in the questions or any feelings I may have about the person asking the questions. I just look at the verses, do my best to understand and accept what they plainly say, and only then do I consider the questions and the arguments implicit in the questions.
This produced really pleasant results today, at least in my mind. My response settled and finalized some things I have already been considering because of how unique the apostle John's writings are.
In reference to Col 2:14, the NASB and NIV agree with you that the "handwriting of ordinances" is debt, but Meyer's NT commentary says they are wrong, "What is thus characterized is NOT the burden of debt lying upon man, which is, as it were, his debt-schedule (Bleek), but the Mosaic law."
Nonetheless, even if it were debt, Jesus addresses this directly in a parable. I'm sure you know it. The servant's debt was forgiven, but then it was reinstated when he would not forgive a fellow servant a much smaller sum (Matt. 18:23-35).
Then you asked, "Is final justification the receiving of what was ours all along?"
According to John, yes. According to all the other NT writers, no. John is the only NT writer who speaks of eternal life as a present possession (e.g., John 6:47). For Paul, it is a future reward (Rom. 2:6-7; Gal. 6:7-9; Rom. 6:22-23, etc.). John has a unique focus on the present, much more so than the rest of the New Testament. Thus, in John's Gospel and letters, whatever is true now is true always. Thus, 1 John 2:19 and "they were never of us" is typical of his writing, not exceptional.
In the specific case of 1 John 2:19, the Gospels seem to concur. Jesus "never knew" those who did mighty works in his name but lived in iniquity (Matt. 7:23). The bridegroom did not know the five virgins whose oil ran out even though they were expecting to be married to him (Matt. 25:1-13).
That's a difficult thought to explain, but if we just accept the teaching at face value, without explanation—as I always prefer to do—we must say that those who receive the Holy Spirit (the oil of the virgins), if they fall away, are regarded as never known. That is no contradiction to Paul's repeated statements that eternal life will only be rewarded to those who have holiness because of living righteously (Rom. 6:22) and to those who have not grown weary in doing good works by sowing to the Spirit (Rom. 2:6-7; Gal. 6:8-9; Rom. 8:12-13).
It seems obvious to me that in response to the things we have just looked at, which involves simply accepting what Scripture directly says, we should obey Peter and diligently "do these things" so we can make our calling and election sure. Peter would never tell us to do that if our calling and election were already sure. "These things" that he tells us to do "diligently" in both 2 Peter 1:5 and 1:10 are to "add to our faith virtue, to virtue knowledge, to knowledge self-control, to self-control perseverance, to perseverance godliness, to godliness brotherly-kindness, and to brotherly-kindness love" (1 Pet. 1:5-7).
Faith brought us grace that breaks the power of sin (Rom. 6:14) and teaches us to deny ungodliness and worldly lusts (Tit. 2:11-12), and I suspect we agree that grace is implemented by the Holy Spirit, whom we are following if we are children of God (Rom. 8:14). Thus we are provided everything that pertains to life and godliness and, with nothing but our beginning in faith, we have escaped the corruption that is in the world though lust (2 Pet. 1:3-4). Because of "amazing grace" and the Holy Spirit, we are able to obey Peter and diligently add to our faith so we can make our calling and election sure and obtain an "abundant entrance" into the kingdom of our Lord and Savior Jesus Christ (2 Pet. 1:10-11).
Of course, Paul warns us that if we do not do what Peter describes, but instead practice the works of the flesh, we will reap corruption (Gal. 6:7), and we will have no inheritance in the kingdom of God and Christ, but will instead experience the wrath that comes upon the sons of disobedience (Eph. 5:3-7; cf. 1 Cor. 6:9-11; Gal. 5:19-21).
We can argue whether "never knew you" implies a person was never saved, but that is the past. The present and future for us is that Peter told us to diligently confirm our calling and election by supplying virtue, knowledge, etc. in our faith. Until then, Peter says that anyone who addresses God as Father should conduct themselves in fear because one day he will impartially judge according to each one's work (1 Pet. 1:17).
The fact is that at one time, at the earliest known point in church history, the couple centuries after the apostles, everyone wrote like I am writing here. Modern Christians accuse them of legalism, even claiming all the apostles' churches fell away, but look at all the Scripture I gave above without having to explain anything away! Let us consider that we are guilty of turning grace into a license for sin, but either way, let us obey the command of Scripture to diligently do these things to make our calling and election sure.
The early churches believed that even our righteousness was a gift from God, impossible without the atonement of Christ and the power of the Spirit. Ignoring that gift of "freedom from sin" (Rom. 6:22) will not lead to eternal life. Instead rejoicing with joy unspeakable and full of glory and cleansing ourselves from every defilement of flesh and spirit (2 Cor. 7:1) is the appropriate response. If we do so, living in the light, exposing our deeds to God, then he will give us fellowship with one another, and the blood of Jesus will cleanse all our sins (1 Jn. 1:7).