I disagree to ''grieve the Holy Spirit'' can lose salvation. That is your interpretation and wording.
''Every branch in me that beareth not fruit he taketh away: and every branch that beareth fruit, he purgeth it, that it may bring forth more fruit.''
So this verse about bearing no fruit has no mention about salvation loss,only disappoint about lack of productivity.
''If a man abide not in me, he is cast forth as a branch, and is withered; and men gather them, and cast them into the fire, and they are burned.''
To ''abide'' in Christ is to dwell or believe in Christ. Of course non-believers are condemned,again not a loss of salvation but referring to the unsaved who are not abiding in Christ.
17And if some of the branches be broken off, and thou, being a wild olive tree, wert grafted in among them, and with them partakest of the root and fatness of the olive tree;
18 Boast not against the branches. But if thou boast, thou bearest not the root, but the root thee.
19 Thou wilt say then, The branches were broken off, that I might be grafted in.
20 Well; because of unbelief they were broken off, and thou standest by faith. Be not highminded, but fear:
21 For if God spared not the natural branches, take heed lest he also spare not thee.
22 Behold therefore the goodness and severity of God: on them which fell, severity; but toward thee, goodness, if thou continue in his goodness: otherwise thou also shalt be cut off.
23 And they also, if they abide not still in unbelief, shall be grafted in: for God is able to graft them in again.
In Pauls letter the people who were ''broken off'' did so because of the lack of faith. It was never there to begin with-they probably trusted in self-works for salvation.
11 It is a faithful saying: For if we be dead with him, we shall also live with him:
12 If we suffer, we shall also reign with him: if we deny him, he also will deny us:
13 If we believe not, yet he abideth faithful: he cannot deny himself.
Denying Christ in this context is rejecting him as Savior=unsaved. The genuine believers who actually see Christ as their savior call out to him in faith and are saved,eternally.