It's Impossible to be a Christian and Not Bear Even ONE Good Fruit for the Lord Jesus Christ
First and foremost, anybody who does not believe in the heresy of works salvation is NOT an Antinomian (anybody who has no regard of morality) because born again believers do not add works to being saved like cultists do. However, there is a difference between being saved by faith and what happens. In the Christian life, it is not a stagnant "just look up and wait for Jesus" type of life. Why? The Lord Jesus mentioned in Matthew 7:17-20 saying, "Even so every good tree bringeth forth good fruit but a corrupt tree bringeth forth evil fruit. A good tree cannot bring forth evil fruit neither can a corrupt tree bring good fruit. Every tree that bringeth not forth good fruit is hewn down and cast into the fire. Wherefore by their fruits ye shall know them." How does this connect? It's time to review salvation according to the Bible.
So in Romans 3, one sees the reality of sinful state of man, the helplessness of man's efforts and that the Lord Jesus Christ is the solution to the problem. The last verse which is Romans 3:31 saying, "Do we then make void the Law through faith? God forbid: yea we establish the Law." That means, it's obedience because disobedience does not establish the Law. Instead, Christians by God's grace cannot boast of anything as Romans 3:27 says, "Where is boasting then? It is excluded. By what law? Of works? Nay but by the law of faith." Romans 4:5 saying, "But to him that worketh not but believeth upon Him which justifieth the ungodly, his faith is counted for righteousness." would mean, that faith would count (included) for righteousness, meaning it results to righteousness. Righteousness manifests to real good deeds, not good deeds done in an attempt to please God to enter Heaven their way. How does it work? Faith results to good works. Read Hebrews 11 and James 2 and see what good works came as a result of believing upon Him which justifies the ungodly. Anybody who tries to do good works to enter Heaven is a fruit thief.
So going down, salvation is by grace through faith but it does not stop there. Ephesians 2:10 can be missed out so easily which says, "For we are His workmanship created in Christ Jesus unto good works which God hath before ordained that we should walk in them." and Titus 2:11-14 says, "For the grace of God that bringeth salvation hath appeared unto all men, teaching us that, denying ungodliness, and worldly lusts, we should live soberly, righteously, and godly in this present world; looking for that blessed hope and the glorious appearing of theg reat God and our Savior Jesus Christ; who gave Himself for us that He might redeem us from all iniquity and purify unto Himself a pecular people zealous of good works." That is God's grace is no license to sin, rather it rebukes sin. Why? It's because Jesus Christ is their Lord and Savior. Lord because He chastises them when they screw up (Hebrews 12:5-6) yet Savior because He didn't cast them out (John 6:37).
In James 2, it does not teach works salvation but rather the effects of salvation. James 2:10-11 shows the impossibility of works salvation. On the other hand, James 2:18 is a challenge for every believer saying, "Yea a man may say, Thou hast faith and I ahve works: show me thy faith without thy works and I will show thee my faith by my works." Which of course, James 2:23-24 is clear in showing what salvation does saying, "And the Scripture was fulfilled which saith Abraham believed God and it was imputed into him for righteousness and he was called the friend of God. Ye see then how that by works a man is justified and not by faith only." By the way, justification means to be made right, which by works, a man's claims to being saved is being justified by his actions.
There can be a difference between the carnality of Christians vs. the carnality of the unsaved. Carnal Christians can be very ashamed of who they are to the point, they would be sinning more secretly, trying to hide lest they become a stumbling block to others, most of the time making sure nobody is around but God as their witness. On the other hand, carnal unbelievers most of the time sin without shame. Just take a look at the media today- we have atheist scientists curse the Creator of science without shame, we have porn stars pose naked without shame, we have rock stars rocking for Satan without shame. These types of evil would make even the most carnal of Christians feel bad like Lot in Sodom as 1 Peter 2:7 says, "And delivered just Lot vexed with the filthy conversatiom of the wicked:" which he though a backslider, was horribly disturbed of Sodom.
Therefore there is ground to DOUBT that anybody who claims to be a Christian and have no good works. Why? 1 John 2:3-5 says, "And hereby we do know that we know Him, if we keep His commandments. He that saith, I know Him, and keepeth not his commandments, is a liar, and the truth is not in him. But whoso keepeth his word, in him verily is the love of God perfected: hereby know we that we are in Him. He that saith he abideth in Him ought himself also so to walk, even as He walked." As said, if you are a Christian then ACT LIKE ONE- follow Jesus MORE! That is, keep God's commandments. Again, this is not works salvation but rather the evidences of salvation. This is talking of the fruit. 1 John 2:19 again shows the manifestation of the phonies vs. the genuine Christians- those who claimed to be Christians but had no fruit were not Christians. Again this goes back to Matthew 5:17-20. As said, the first act of obedience was to repent and believe the Gospel and to get saved which of course, results to more obedience.
Now to close with John 15:1-10 in which the Lord Jesus talks about bearing fruit. It would be natural to assume verse 6 would count for the unsaved, one who abides not in Jesus Christ. Again, why would an unbeliever abide in Jesus Christ if he/she doesn't even trust in Him for salvation as He so commands? Christians abide in their Lord Jesus Christ but most inconsistent (which of course the struggle against sin still happens and Christians at best will still sin but there's a DIFFERENT attitude though) so He does everything to prune them to be more fruitful and remove every sin at every moment they sin. Galatians 5:22-23 describes the fruits of the Holy Spirit in the life of the believer which are love, joy, peace, patience, kindness, goodness, meekness and temperance which is quite different from the fruits of the flesh. Since Christians are still bound to the flesh, it would be crazy for them to rely on their own strength to overcome. Instead, they can be confident that the new man born of God sins not and it's by God's working in them (Philippians 2:13) and not of themselves that should be the guidance of their actions and proper use of freewill as for the Christian, perfection is a daily task and commanded as a means to lead others to the Lord Jesus Christ.