John 15 is talking to people who hadn't yet receive the Spirit and as such had not been born God. "Up to that time the Spirit had not been given, since Jesus had not yet been glorified." John 7:39 And "if anyone does not have the Spirit of Christ, he does not belong to Christ." Rom 8:9 Of those who do not belong to Christ it is written, "They went out from us, but they did not really belong to us. For if they had belonged to us, they would have remained with us; but their going showed that none of them belonged to us." 1John 2:19
Romans 11 is talking about Gentiles as a category, not about individual believers.
As for Eph 5:5, which is similar to 1Cor 6:9,10 it's not talking about losing salvation - or as you "faith in works Christian" believe - that salvation is contingent upon one's ongoing performance. Rather these are describing behaviors of the unsaved, those have not been born of God. For it says of those who have been born of God "No one who is born of God will continue to sin, because God’s seed remains in him; he cannot go on sinning, because he has been born of God. This is how we know who the children of God are and who the children of the devil are: Anyone who does not do what is right is not a child of God; nor is anyone who does not love his brother." 1John 3:9,10 Thus those children of the devil who have infiltrated the ranks of the Christianity community can be identified by their behavior
So your saying Jesus’ 11 faithful apostles didn’t belong to Christ? How could they abide in Christ if they did not belong to Him? Your quote of first Romans 8:9 is after Pentecost. The apostles didn’t need the Holy Spirit at that time because they had Jesus to guide them who kept them by His power and the very same night just a few moments after John 15 in John 17 Jesus prays asking The Father Himself to keep them from falling and even said to them
“No longer do I call you slaves, for the slave does not know what his master is doing; but I have called you friends, for all things that I have heard from My Father I have made known to you. You did not choose Me but I chose you, and appointed you that you would go and bear fruit, and that your fruit would remain, so that whatever you ask of the Father in My name He may give to you. This I command you, that you love one another. "If the world hates you, you know that it has hated Me before it hated you. If you were of the world, the world would love its own; but because you are not of the world, but I chose you out of the world, because of this the world hates you. Remember the word that I said to you, 'A slave is not greater than his master.' If they persecuted Me, they will also persecute you; if they kept My word, they will keep yours also.”
JOHN 15:15-20 NASB
Your explanation of Romans 11 is incorrect my friend.
“Behold then the kindness and severity of God;
to those who fell, severity, but to you, God's kindness,
if you continue in His kindness; otherwise you also will be cut off.”
ROMANS 11:22 NASB
All of the Jews were not cut off, only those who didn’t believe in Christ were cut off, and God does not cut off all Gentiles because of individuals who fail to believe. So again I maintain that Paul is in fact warning individuals who were grafted in of being cut off and can be grafted in again if they repent. This message is not specifically only for groups of gentiles or Jews.
Now concerning Ephesians 5 let’s not simply take verse 5 by itself out of the context of the message. That’s the biggest problem with those who advocate OSAS. They take bits and pieces of the message disregarding that parts that refute OSAS. Paul is warning children of God of receiving the wrath of God on the sons of disobedience which is they will have no inheritance in the kingdom of God.
“But immorality or any impurity or greed must not even be named among you, as is proper among saints; and there must be no filthiness and silly talk, or coarse jesting, which are not fitting, but rather giving of thanks.
For this you know with certainty, that no immoral or impure person or covetous man, who is an idolater, has an inheritance in the kingdom of Christ and God. Let no one deceive you with empty words,
for because of these things the wrath of God comes upon the sons of disobedience.”
EPHESIANS 5:3-6 NASB
Again your not reading 1 John 3:9-10 in the proper context. As Paul has shown in Ephesians 5 a child of God can become a son of disobedience and suffer God’s wrath resulting in loss of salvation.
There is no exclusion of believers anywhere in these messages.
When you follow the desires of your sinful nature, the results are very clear: sexual immorality, impurity, lustful pleasures, idolatry, sorcery, hostility, quarreling, jealousy, outbursts of anger, selfish ambition, dissension, division, envy, drunkenness, wild parties, and other sins like these. Let me tell you again, as I have before, that
ANYONE living that sort of life will not inherit the Kingdom of God.
Galatians 5:19-21
Even now the ax of God’s judgment is poised, ready to sever the roots of the trees. Yes,
EVERY TREE that does not produce good fruit will be chopped down and thrown into the fire.
Matthew 3:10
Nothing evil will be allowed to enter,
nor ANYONE who practices shameful idolatry and dishonesty—but only those whose names are written in the Lamb’s Book of Life.
Revelation 21:27
A faithful, sensible servant is one to whom the master can give the responsibility of managing his other household servants and feeding them. If the master returns and finds that the servant has done a good job, there will be a reward. I tell you the truth, the master will put that servant in charge of all he owns. But what if the servant is evil and thinks, ‘My master won’t be back for a while,’ and he begins beating the other servants, partying, and getting drunk? The master will return unannounced and unexpected, and he will cut the servant to pieces and assign him a place with the hypocrites. In that place there will be weeping and gnashing of teeth.
Matthew 24:45-51
A servant of the master is a servant of God. This is not referring to unbelievers. Unbelievers do not serve God.
or as you "faith in works Christian" believe - that salvation is contingent upon one's ongoing performance.
No I’m saying one’s ongoing performance must reflect their faith. A lack of works shows a lack of faith and indicates the person is not abiding in Christ and Christ is not abiding in Him. Jesus said anyone who abides in Him will bear much fruit. He didn’t say they might bear fruit or they may bear a little fruit. The words He said was “they WILL bear MUCH FRUIT”.