Do we need to believe that salvation cannot be earned to be saved?

from the old testament

• The Old Testament repeatedly shows that righteousness before God is not achieved by human effort. Even figures like Abraham are counted righteous because of faith, not works (Genesis 15:6). This is a key example that acceptance before God has always been based on trusting Him, not earning favor.
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• The sacrificial system in the Law (Leviticus 1–7) highlights that sin requires atonement provided by God, not achieved by human achievement. The people did not “earn” forgiveness; they received it through God’s appointed means of sacrifice, pointing to their dependence on Him.
• The prophets consistently reject the idea that external religious effort can replace a transformed heart. Isaiah emphasizes that human righteousness is insufficient and that salvation comes from the Lord’s initiative, not human performance (Isaiah 64:6; Isaiah 43:11).

from the new testament

• Historically, Christians have referred to salvation as being sola fide, meaning by “faith alone.” This contrasts with beliefs held by some parts of Christendom and other religions that salvation can be earned to some degree. However, the doctrine of "sola fide" comes from Scripture’s teaching that salvation is through faith alone.
• Paul also teaches that “the one who does not work but believes in [God] who justifies the ungodly, his faith is counted as righteousness” (Romans 4:5). In that passage, he was explaining to Jews who appealed to obedience to the Mosaic Law as required for salvation that their forefather Abraham never had the Law, yet was counted righteous because of his faith in God’s promise (Romans 4:9–22). Paul then notes, “That is why his faith was ‘counted to him as righteousness.’ But the words ‘it was counted to him’ were not written for his sake alone, but for ours also. It will be counted to us who believe in him who raised from the dead Jesus our Lord, who was delivered up for our trespasses and raised for our justification” (Romans 4:22–25).
• Salvation, then, is faith in God’s promise that Jesus’ life, death, and resurrection provide salvation for sinners. A sinner is anyone who is not perfect like God (Matthew 5:48). The problem is that breaking even one of God’s laws means we are not perfect and are under His wrath. Paul warned believers who were tempted to add obedience to the Mosaic Law that if they tried, “Cursed be everyone who does not abide by all things written in the Book of the Law, and do them” (Galatians 3:10). Likewise, James points out that “whoever keeps the whole law but fails in one point has become guilty of all of it” (James 2:10). In order to earn salvation, someone must be perfect. The moment they fail at any point, they are guilty of rebellion, under God’s wrath (John 3:36), and unable to save themselves.
• Since everyone is a sinner (Romans 3:23), no one even has the option, let alone the ability, to live perfectly. Because we owe a debt we cannot pay (Colossians 2:13–14), we need another way to be saved. This is why God sent His Son, Jesus. Jesus, who is eternally God (John 1:1), took on humanity to also be fully human (Philippians 2:6–7). Being fully human, He was exactly like us in every way, except He never sinned (Hebrews 4:15). What we could not do—keep the entire Law—He did. Since the penalty for sin is death (Romans 6:23a), Jesus did not have to die. However, He willingly died as a substitute for repentant men and women, taking the punishment they deserved (2 Corinthians 5:21; 1 Peter 3:18).
• Because Jesus is the only one to have ever lived perfectly, He is also the only way to be saved. That is why He said, “I am the way, and the truth, and the life. No one comes to the Father except through me” (John 14:6). Trying to earn our salvation is endeavoring to follow a path to heaven that doesn’t exist!
• However, though Scripture is clear that we cannot earn our way to salvation, the question is whether it is possible for us to mistakenly think we can and still be saved. Jesus described the type of faith required to please God: a childlike faith (Matthew 18:3). Just as a child can have a mistaken view of something, so can a new, immature believer. It is possible that such a believer could think that what they do determines whether they are saved.
• In Galatians, Paul was dealing with believers who were being tempted to think that way. While he had a strong warning against that (Galatians 1:6–9), he still lovingly taught them the implications of their error (Galatians 4:9–11), that obedience to the Law negated their salvation, not enhanced it (Galatians 5:2–4).
• Similarly, we need to be gracious with new believers who might be tempted in the same way. However, since Scripture strongly warns that any gospel other than the one of free grace is damning (Galatians 1:6–9), anyone who persistently and intentionally holds to the possibility of salvation through works proves that they are not saved. This is because, to be saved, we need to confess who Jesus is (Romans 10:9–10), and such statements demonstrate self-righteousness (Romans 10:3–4) and a lack of understanding of who He is or why He came. That is why Paul strongly warned that the one who holds such a belief is “severed from Christ, you who would be justified by the law; you have fallen away from grace” (Galatians 5:4).

implications for today

Salvation is a gift from God (Ephesians 2:8–9). Being a gift means it cannot be earned. In fact, Paul notes that sin, not salvation, is what we earn (Romans 6:23a). Every religion except for Christianity is based on the belief that salvation can be earned. Even the “nones,” those who claim to have no religious affiliation, still view their good works in a favorable light. This is because people misunderstand sin and salvation.

Sin is doing anything contrary to what God commands. Another word for that is rebellion. Every sinful act we commit is us, as creatures, thumbing our noses at God, our Creator. Rebellion requires punishment. Our works, good or otherwise, do not affect that. Consider a bank robber, for example. When caught, he cannot plead his case by saying he is a good person or by doing nice things. Regardless of what he says or does, he has still robbed a bank and must be punished for that crime.

Likewise, it does not matter whether we are charitable, kind to others, or do a bunch of religious activities. We still have the crime of rebellion hanging over us, and God must punish us for that crime. True justice does not allow someone to buy themselves out of judgment, and since God is perfectly just, He is not appeased by what we do.

However, out of mercy, He sent His Son, Jesus. He placed the sins of repentant men and women on Jesus and then poured out the full punishment they deserved on Him. Salvation is receiving Jesus’ substitutionary death by repenting of sin and trusting that Jesus has already paid the penalty. That is the only way one can be saved.