You said, "
faith (saving faith)
is the establishment" of our communion with God, but that's not the end of the matter, is it? Faith (sanctifying faith) is one of the things that is at the heart of our new and ongoing life in Christ, yes, to our growing communion/relationship with Him, as He enables us to come alongside of/work together with Him toward our sanctification .. e.g.
Romans 1:17; Philippians 1:6, 2:12-13?
Yes-it most certainly isn't the end of the matter but the
beginning, in fact, the beginning of a new life of union with God, the beginning of life eternal, the beginning of the salvation that we work out together with He who works in us to the extent that we remain in Him and He in us.
While we both agree that our salvation is dependent upon our sins being "imputed" or credited to our Savior's account (because He becomes "sin" not a "sinner" on our behalf), the same (at least to my present understanding anyway) cannot be said about the other side of the coin (if you will), IOW, that His righteousness is imputed/credited to 'our' accounts, and yet, that seems to be what you said in your last post. Yes?/No?
Yes, this is sort of the heart of the matter-and the main reason that Sola Fide can be confusing. By Christ’s sacrifice and our faith in Him and His work we’re justified-
made just. We’re forgiven, cleansed, washed,
and made new creations, enabled to 'go, and sin no more', because we’ve been
given righteous; we’re not merely snow-covered dung-heaps which is effectively no different than white-washed tombs, clean on the outside while still dirty on the inside. The new covenant is about real change, with the “righteousness of God” imparted or infused. So read Phil 3:9 in light of that understanding:
“…not having a righteousness of my own that comes from the law, but that which is through faith in Christ—the righteousness that comes from God on the basis of faith.”
And,
“For it is not those who hear the law who are righteous in God’s sight, but it is those who obey the law who will be declared righteous.” Rom 2:13
“But now the righteousness of God has been manifested apart from the law, although the Law and the Prophets bear witness to it.” Rom 3:21
“Therefore, since we have been justified through faith, we have peace with God through our Lord Jesus Christ, through whom we have gained access by faith into this grace in which we now stand.“ Rom 5:1-2
“…just as sin reigned in death, so also grace might reign through righteousness to bring eternal life through Jesus Christ our Lord.” Rom 5:21
“For we know that our old self was crucified with him so that the body ruled by sin might be done away with, that we should no longer be slaves to sin— because anyone who has died has been set free from sin.” Rom 6:6
"And so he condemned sin in the flesh, in order that the righteous requirement of the law might be fully met in us, who do not live according to the flesh but according to the Spirit." Rom 8:3-4
“Therefore, brothers and sisters, we have an obligation—but it is not to the flesh, to live according to it. For if you live according to the flesh, you will die; but if by the Spirit you put to death the misdeeds of the body, you will live.” Rom 8:12-13
“This is the message we have heard from him and declare to you: God is light; in him there is no darkness at all. If we claim to have fellowship with him and yet walk in the darkness, we lie and do not live out the truth. But if we walk in the light, as he is in the light, we have fellowship with one another, and the blood of Jesus, his Son, purifies us from all sin.” 1 John 1:5-7
The basis or essence of man’s unrighteousness is separation or disassociation from God. The basis of man's righteousness is communion with God. Within that union or fellowship God does a work in us, of placing His law in our minds and writing it on our hearts. Historically the justice or righteousness that is said to be infused into man are the virtues of faith, hope, and love, with love being the most important, arguably encompassing the others anyway.
As Paul put it in 1 Cor 13:
“…if I have a faith that can move mountains but have not love, I am nothing.”
And Augustine could later say,
“Without love faith may indeed exist, but avails nothing.”
So,
“And hope does not put us to shame, because God’s love has been poured out into our hearts through the Holy Spirit, who has been given to us.” Rom 5:5
And love, of course, fulfills the law (Rom 13:10). We have to understand that faith is not the equivalent of righteousness for man, nor is it a replacement for it nor is it a license to be free from the
obligation to be righteous. Rather, it’s the authentic
means to righteousness for man because it’s the means, the doorway, to the Author of true goodness and righteousness.
“Apart from Me you can do nothing” (John 15:5). Faith is all about being
with Him.
And to a Catholic there's no real difference between justification and sanctification; it's all part of the same process. Once justified we're to begin to walk and talk like it, like children of God, and continue to do so while expected to grow even more in holiness, in nearness to Him, and definitely not turn sharply back away even though there's reconciliation to be had for that, for repentant hearts, if necessary.