Coming to the Lord for the first time in being saved by God's grace, doesn't really amount to anything according to what you wrote below.
Sure it does because the reason Christ died for us was so that He might sanctify and cleanse it with the washing of the water by the word (Scripture) that He might present to Himself a glorious church that should be holy and without blemish and without spot.
“...even as Christ also loved the church, and gave himself for it; That he might sanctify and cleanse it with the washing of water by the word, That he might present it to himself a glorious church, not having spot, or wrinkle, or any such thing; but that it should be holy and without blemish.” (Ephesians 5:25-27).
“Who gave himself for us, that he might redeem us from all iniquity, and purify unto himself a peculiar people, zealous of good works.” (Titus 2:14).
“...God hath from the beginning chosen you to salvation through sanctification of the Spirit and belief of the truth” (2 Thessalonians 2:13).
But most Christians today do not receive and accept these above verses.
They try to insert a belief into the Bible that says they can sin and still be saved on some level.
They believe they can serve two masters (i.e. Both God and their sin).
You said:
It seems according to that, the way you're using it, you still have to perform well enough to earn eternal life. Most Christians seem to think what separates Christianity from Islam and Hinduism etc is that it's not based on works.
Well, salvation is not a one size fits all package deal. Many can be saved soley by God's grace alone. I believe those who die on their deathbed can receive Jesus as their Savior. I believe babies who are aborted can be saved even without faith. But Jesus said, to whom much is given, much is required.
Christians are initially and foundationally saved by God's grace through believing and trusting in Jesus Christ as the Savior. A person is foundationally or ultimately saved by God’s grace because if they happen to sin on rare occasion in their Christian walk, they do not do a good work to absolve that sin, but they confess of their sins to Jesus in order to be forgiven of that sin (1 John 1:9) (1 John 2:1) (Hebrews 4:16) (For verses on being saved by God's grace, see: Ephesians 2:8-9, Romans 4:1-6, Titus 3:4-7, 1 Corinthians 15:1-4, Luke 18:9-14, Romans 5:1-2). This does not lead to an endless cycle of sinning and confessing one's whole life (with no real change in a person's life) whereby they are just paying empty lip service while they justify sin.
For we are told to work out our salvation with fear and trembling (Philippians 2:12), which is in context to God doing the good work through us to will and do of His good pleasure (Philippians 2:13).
After we are saved by God's grace, we know the Bible also teaches....
- We are justified by works and not by faith alone (James 2:24).
- Faith without works is dead (James 2:17).
- A person can deny God by a lack of works (Titus 1:16).
- Jesus agreed with the lawyer that to love God, and to love your neighbor is a part of inheriting eternal life (Luke 10:25-28).
- Those who have done good, shall come forth unto the resurrection of life; and those who have done evil, shall come forth unto the resurrection of damnation (John 5:29).
- We have to continue in His goodness, otherwise we can be cut off [just like the Jews were cut off] (Romans 11:21-22).
- Helping the poor, and the unfortunate relates to inheriting the Kingdom (Matthew 25:34-40), and not helping the poor, and the unfortunate relates to going away into everlasting punishment (Matthew 25:41-46).
- Whoever does not righteousness or does not love his brother is not of God (1 John 3:10).
- Whoever does what Jesus says is likened unto a wise man who built his house upon the rock, and when a storm came, it did not fall, (Matthew 7:24-25), but the person who does not do what Jesus says is likened unto a fool who built his house upon the sand, and when a storm came, great was the fall of that house (Matthew 7:26-27).
- Abiding in Jesus will bear much fruit, but if a person does not abide in Jesus [thereby being unfruitful], they are cast out [or cut off] like a branch to be burned in the fire (John 15:5-6).
- If the righteous scarcely be saved, where shall the ungodly and the sinner appear? Wherefore let them that suffer according to the will of God commit the keeping of their souls to him in well doing (1 Peter 4:18-19).
- Pursue peace with all people, and holiness, without which no one will see the Lord (Hebrews 12:14) (NKJV).
So salvation is not as one dimensional as many would like to believe. Yes, salvation is not by Works Alone without God's grace because nobody can be saved without their past slate of sin being wiped out by God's grace through faith in Christ. There are many who believe in God and they have not accepted Jesus as their Savior. They think they are worthy of Heaven based soley on their good deeds outweighing their bad deeds on some sort of cosmic judgment scale by God. But salvation does not work like that. Nobody's good deeds alone (without God's grace) can be worthy enough to cleanse their own sin. Only by the blood of Jesus Christ and in believing and trusting in Him can our past sins be forgiven and or cleansed. But after we are saved by God's grace, we need to also walk in the light as He is in the light and the blood of Jesus cleanses us from all sin, too (See: 1 John 1:7). For God's grace is not a license for immorality or in turning His grace into lasciviousness or lustfulness (Jude 1:4). Believers do have to also enter the Sanctification Process in putting away sin, and in being fruitful for their Lord, and they cannot justify sin after being saved by God's grace.
So salvation is not in Works Alone and neither is it in Grace Alone if they live out their faith. Salvation is not as overly simplistic as you are making it out to be. God does require us to actually obey Him as a part of eternal life (See: Hebrews 5:9). This would be obeying Him in being saved by God's grace, and in entering the Sanctification Process. But many Christians today think they just need a belief alone in Jesus to be saved, and that lifting a finger for God and doing good as a part of being in His Kingdom is wrong. Thus, this means that a believer can do evil in the name of the Lord and be saved on some level. For the opposite of doing good is doing evil. To remain in a state of doing nothing for the Lord is to be one's own lord and master instead of making Jesus their Lord. They do not have to love the Lord in living a pure life for Him and in being fruitful. They can sin and still be saved on some level. That's what this is really about.