God gave His law to define right and wrong, reveal sin, teach people how to love God and others, and show a way of life that is good for humanity. The law cannot save us; salvation is God’s gift through Jesus Christ. But God’s law reveals the righteous standard by which Christians learn how God wants them to live.
Many Christians have heard that God’s law belongs primarily to the Old Testament—that it was given to ancient Israel but has little relevance for Christians living under grace.
But before asking whether Christians should obey God’s law today, there is a more fundamental question:
Why did God give the law in the first place?
Was God’s law an arbitrary collection of restrictions? Was it merely a temporary system designed for ancient Israel? Or does God’s law reveal something much deeper about God, sin, love, and the way human beings were created to live?
The Bible presents God’s law not as a burden designed to make life difficult, but as instruction from a loving Creator who knows what is good for His creation.
Understanding why God gave the law helps us understand why Jesus taught obedience, why the apostles defined sin in relation to God’s law, and why the New Covenant promises to write God’s laws in the hearts and minds of God’s people.
God’s Law Reveals the Difference Between Right and Wrong
One of the most basic purposes of God’s law is to define sin.
The apostle John wrote:
“Sin is the transgression of the law” (1 John 3:4, KJV).
Paul similarly explained:
“I would not have known sin except through the law” (Romans 7:7).
Without a standard, how could we objectively determine what is right and wrong?
Human societies establish their own moral standards, but those standards continually change. Practices once considered wrong may later become acceptable, while other behaviors may be condemned according to changing cultural values.
God’s standard does not depend upon popular opinion.
His law identifies behavior that reflects His righteous character and exposes behavior that is contrary to it.
Paul therefore wrote:
“Therefore the law is holy, and the commandment holy and just and good” (Romans 7:12).
God did not give His law because the law was evil. He gave it because human beings needed His instruction concerning good and evil.
God Gave His Law for Our Good
Sometimes God’s commandments are portrayed primarily as restrictions—things God does not allow us to do.
Moses described them very differently.
He told Israel:
“And the LORD commanded us to observe all these statutes, to fear the LORD our God, for our good always, that He might preserve us alive” (Deuteronomy 6:24).
Notice the phrase:
“For our good always.”
God’s commandments were intended for human well-being.
A loving parent establishes boundaries because the parent understands dangers that a child may not yet recognize. In a much greater way, God understands the consequences of human choices far better than we do.
He created human beings. He understands how relationships, families, communities, and societies function best.
His instructions concerning honesty, marriage, sexuality, property, worship, justice, rest, respect for parents, and love for others are not arbitrary rules.
They reveal a way of life.
Moses later explained:
“And now, Israel, what does the LORD your God require of you, but to fear the LORD your God, to walk in all His ways and to love Him…and to keep the commandments of the LORD and His statutes which I command you today for your good?” (Deuteronomy 10:12–13).
Again, obedience and human good are connected.
God’s Law Teaches Us How to Love
Jesus summarized God’s law using two great commandments.
When asked which was the greatest commandment, He answered:
“You shall love the LORD your God with all your heart, with all your soul, and with all your mind” (Matthew 22:37).
Then He added:
“You shall love your neighbor as yourself” (verse 39).
Jesus concluded:
“On these two commandments hang all the Law and the Prophets” (verse 40).
Jesus did not contrast love with God’s law.
He showed that love summarizes the purpose of God’s law.
The Ten Commandments demonstrate this beautifully.
The first commandments teach us how to properly honor and worship God. The remaining commandments govern our relationships with other people—honoring parents, respecting life, protecting marriage, respecting property, speaking truthfully, and controlling selfish desires.
Paul expressed the same principle:
“Love does no harm to a neighbor; therefore love is the fulfillment of the law” (Romans 13:10).
Biblical love is more than an emotion.
God’s law helps define what love looks like in action.
God’s Law Reveals God’s Character
God’s commandments also teach us something about the One who gave them.
The Bible describes God as righteous:
“The LORD is righteous in all His ways, gracious in all His works” (Psalm 145:17).
God’s law is likewise described as righteous:
“All Your commandments are righteousness” (Psalm 119:172).
God is holy, righteous, faithful, truthful, and loving. His law reflects those same qualities.
This helps explain why Scripture repeatedly speaks positively about God’s commandments.
The psalmist wrote:
“Oh, how I love Your law! It is my meditation all the day” (Psalm 119:97).
He did not view God’s law merely as a list of restrictions. He saw God’s instruction as wisdom coming from God.
The more we understand God’s way, the more we understand something about God’s mind and character.
The Law Shows Us Our Need for a Savior
God’s law can identify sin, but it cannot erase sins we have already committed.
This distinction is essential.
Paul wrote:
“By the law is the knowledge of sin” (Romans 3:20).
Imagine looking into a mirror and discovering dirt on your face. The mirror reveals the problem, but the mirror cannot wash your face.
Similarly, God’s law reveals sin, but keeping the law afterward cannot erase previous sin.
Forgiveness requires something else.
It requires Jesus Christ.
Scripture tells us:
“For all have sinned and fall short of the glory of God” (Romans 3:23).
And:
“The wages of sin is death, but the gift of God is eternal life in Christ Jesus our Lord” (Romans 6:23).
Christ paid the penalty for our sins.
That is why salvation is a gift of God’s grace and cannot be earned through law-keeping.
Paul wrote:
“For by grace you have been saved through faith…not of works, lest anyone should boast” (Ephesians 2:8–9).
But that does not mean grace makes God’s definition of sin meaningless.
Grace provides forgiveness for breaking God’s law; it does not redefine disobedience as righteousness.
Grace and Obedience Are Not Enemies
One of the most common misunderstandings in Christianity is the idea that grace and obedience must somehow oppose each other.
Paul anticipated this misunderstanding.
After explaining God’s grace, he asked:
“Shall we continue in sin that grace may abound?”
His answer was emphatic:
“Certainly not!” (Romans 6:1–2).
Grace does not give Christians permission to continue knowingly practicing sin.
Instead, grace makes forgiveness and reconciliation with God possible and begins a transformed way of life.
Paul wrote that we are:
“Created in Christ Jesus for good works” (Ephesians 2:10).
Obedience does not purchase salvation.
It is the response of someone who has been forgiven and desires to live according to God’s will.
Jesus Himself connected love with obedience:
“If you love Me, keep My commandments” (John 14:15).
Grace is therefore not God’s permission to ignore His instructions. Grace is God’s undeserved favor toward sinners who could never save themselves.
Did Jesus Come to Abolish God’s Law?
Jesus directly addressed this question in the Sermon on the Mount.
He said:
“Do not think that I came to destroy the Law or the Prophets. I did not come to destroy but to fulfill” (Matthew 5:17).
Jesus then warned against breaking God’s commandments and teaching others to do the same.
19 Whoever therefore breaks one of the least of these commandments, and teaches men so, shall be called least in the kingdom of heaven; but whoever does and teaches them, he shall be called great in the kingdom of heaven (Matthew5:19).
But Jesus did more than simply repeat commandments.
He revealed their deeper spiritual intent.
The command against murder reaches beyond the physical act to hatred and destructive anger (Matthew 5:21–22).
The command against adultery reaches beyond the physical act to lustful intent (Matthew 5:27–28).
Christ fulfilled (magnified) the law by showing that God is concerned not merely with outward behavior but with the heart.
That becomes especially important when we understand the New Covenant.
God’s Law and the New Covenant
The New Covenant is sometimes presented as replacing God’s law.
Yet the Bible’s own description says something very different.
God foretold through Jeremiah:
“I will put My law in their minds, and write it on their hearts” (Jeremiah 31:33).
The book of Hebrews repeats this promise:
“I will put My laws in their mind and write them on their hearts” (Hebrews 8:10).
Notice what God does not say.
He does not say, “I will eliminate My laws.”
Instead, He promises to place His laws within His people.
The problem with the Old Covenant was not that righteousness had somehow become wrong. Human beings lacked the heart necessary to consistently obey God.
Under the New Covenant, God works within converted Christians through His Holy Spirit, transforming their minds and helping them develop His character.
Obedience becomes more than outward conformity.
God wants His way of life written upon the heart.
Does This Mean Christians Keep Every Old Testament Law?
Recognizing the value and continuing importance of God’s law raises an important question:
Does every command given to ancient Israel apply to Christians today in exactly the same way?
No.
The Bible contains different kinds of laws and instructions given within different circumstances.
For example, the sacrificial system pointed forward to Jesus Christ. Christ’s sacrifice fulfilled the need for repeated animal sacrifices (Hebrews 9:11–14; 10:1–14).
Ancient Israel also had civil laws governing a physical nation with judges, property arrangements, penalties, and national institutions.
Christians today are not the civil government of ancient Israel.
Yet these distinctions do not mean God’s moral standards disappeared.
The New Testament repeatedly affirms commandments against idolatry, murder, adultery, stealing, lying, coveting, and other sins.
The proper question therefore is not simply:
“Old Testament or New Testament?”
A better question is:
What was the purpose of this law, and how does the rest of Scripture show that principle applying under the New Covenant?
This is why the Bible must be studied as a unified revelation rather than isolated into disconnected sections.
God’s Law Points Toward a Way of Life
God’s law is ultimately about far more than rules.
It describes a way of life based upon love toward God and love toward other human beings.
Jesus lived that way perfectly.
Christians are called to follow Him.
John wrote:
“He who says he abides in Him ought himself also to walk just as He walked” (1 John 2:6).
God’s purpose is not simply to produce people who know commandments.
He is developing people whose hearts increasingly reflect His own character.
That requires repentance, faith, forgiveness, God’s Holy Spirit, spiritual growth, and obedience.
The law cannot save us.
But the law helps show us what sin is, what love looks like, and how God intends human beings to live.
So Why Did God Give the Law?
The Bible gives several interconnected answers.
God gave His law to define right and wrong, to identify sin, to protect and benefit human beings, to teach us how to love God and one another, and to reveal principles that reflect His righteous character.
The law also shows us how far we fall short and therefore helps us recognize our need for Jesus Christ and God’s grace.
Salvation does not come from keeping the law.
Salvation comes through Jesus Christ as God’s gift.
But the person who has received grace does not therefore ask, “How much of God’s instruction can I disregard?”
A converted Christian increasingly asks:
“How does God want me to live?”
God gave His law, in part, to answer that question.
Key Scriptures to Study
- Deuteronomy 6:24
- Deuteronomy 10:12–13
- Psalm 19:7–11
- Psalm 119:97, 172
- Matthew 5:17–19
- Matthew 22:36–40
- Romans 3:20–23
- Romans 6:1–2, 23
- Romans 7:7, 12
- Romans 13:8–10
- Ephesians 2:8–10
- Hebrews 8:8–10
- 1 John 2:3–6
- 1 John 3:4
Additional Study:
Which Old Testament Laws Should Christians Keep Today?
A Final Encouragement
Don’t simply believe what you read here because someone says it is biblical.
Open your own Bible. Look up the Scriptures for yourself. Read them in context, compare Scripture with Scripture, and believe what the Bible actually says.