Yes, it is a sin not to keep the Sabbath. The Sabbath is one of the Ten Commandments, and the enemy of souls attacks this commandment like no other.
God blessed and sanctified the seventh day, the Sabbath. (Genesis 2:2-3)
He requires that all of us should keep the Sabbath. (John 14:15)
Jesus kept the Sabbath, and the apostles too. (Luke 4:16, Acts 13:42,44, 16:13, 17:2, 18:4)
The Sabbath is still on the seventh day of the week as it always was, and never changed to Sunday as some claim. (Exodus 20:8-11, Matthew 5:17-19)
What happens if you don’t keep the Sabbath?
By not keeping the Sabbath we are guilty of the transgression of God’s holy Law. (James 2:10)
We are sinning if we do not keep the Sabbath. (1 John 3:4)
And the wages of sin is death if we do not repent from it. (Romans 6:23)
But God loves us and forgives us if we repent from our sins, and stop doing them. (1 John 1:9)
Are we required to keep the Sabbath?
Yes, everyone is required to keep the Sabbath because it is the fourth commandment of God. (Exodus 20:8-11), (Mark 2:27)
The Sabbath is to be kept from Friday sundown to Saturday sundown. (Genesis 2:2-3, Leviticus 23:32)
The Sabbath was not done away with as some may think. There is confusion with the Sabbath of the fourth commandment and the sabbath days or the feast days.
The Sabbath of the Fourth Commandment
The seventh day Sabbath is part of the Ten Commandments of God or the moral Law. (Exodus 20:8-11)
This law was created after the six literal creation days. (Genesis 2:2-3)
It was made for everyone. (Mark 2:27)
Jesus kept it and the apostles too. (Luke 4:16, Acts 13:42,44, 16:13, 17:2, 18:4)
Jesus never abolished nor changed the Sabbath day. (Matthew 5:17-19)
The Sabbath days or Feast days
These were part of the law of Moses or the ceremonial laws. They are also called sabbaths.
But they are not to be confused with the Sabbath day from the Ten Commandments, the moral law.
Also in Deuteronomy 31:26, we see that these ceremonial laws were placed on the side of the ark of the covenant.
Take this book of the law, and put it in the side of the ark of the covenant of the LORD your God, that it may be there for a witness against thee.
Deuteronomy 31:26 KJV
These ceremonial laws were written in a book (Deuteronomy 31:24).
However, the Ten Commandments were inside the ark of the covenant and were written in stone. (Exod 25:16, 1 Kings 8:9, Hebrew 9:4)
They are two sets of laws.
In Colossians 2:16, when Paul talks about sabbath days, he refers to the feast days/ceremonial laws, and not to the seventh day Sabbath of the moral law.
The same goes for Romans 14:5.
Is breaking the Sabbath a sin?
Of course. Breaking the Sabbath is a sin, the same as is breaking the other nine commandments. (see Exodus 20)
If we break one law, we are guilty of breaking them all. (James 2:10)
What does the Bible say about keeping the Sabbath in the New Testament?
In the New Testament, we find that keeping the Sabbath is mandatory as it always was.
Jesus kept the Sabbath and healed people on that holy day. (Luke 4:16, Matthew 12:1-12).
He told us He did not come to break the Law, but to fulfill it. (Matthew 5:17-19)
Think not that I am come to destroy the law, or the prophets: I am not come to destroy, but to fulfil.
For verily I say unto you, Till heaven and earth pass, one jot or one tittle shall in no wise pass from the law, till all be fulfilled.
Whosoever therefore shall break one of these least commandments, and shall teach men so, he shall be called the least in the kingdom of heaven: but whosoever shall do and teach them, the same shall be called great in the kingdom of heaven.
Matthew 5:17-19 KJV
The apostles also kept the Sabbath. (Acts 13:42,44, 16:13, 17:2, 18:4)
When Jesus was crucified on Friday, His followers kept holy the next day – Saturday, the Sabbath. (Matthew 28:1, Mark 16:1-2, Luke 23:53-56)
Thus, the Sabbath was never changed nor abolished as some may think or have heard.
Always check the Bible for yourself, not people’s claims.
Did Jesus keep the Sabbath in the New Testament?
Of course Jesus kept the Sabbath in the New Testament. We find many encounters of Him going into the synagogue and doing good on this holy day. (Luke 4:31-37, Matthew 12:1-13).
And he came to Nazareth, where he had been brought up: and, as his custom was, he went into the synagogue on the sabbath day, and stood up for to read.
Luke 4:16 KJV
What is the Sabbath rest in Hebrews 4?
In the books of Hebrew, we also find another reminder of the seventh day Sabbath, and the rest we find in Christ.
For he spake in a certain place of the seventh day on this wise, And God did rest the seventh day from all his works.
Hebrews 4:4 KJV
However, this must not be confused with the fact that Jesus is our rest and we do not need to keep the Sabbath as some teach.
Yes, Jesus gives us rest, and by observing the Sabbath physically we acknowledge that we serve Him and love Him.
He blesses us on the Sabbath day.
If thou turn away thy foot from the sabbath, from doing thy pleasure on my holy day; and call the sabbath a delight, the holy of the LORD, honourable; and shalt honour him, not doing thine own ways, nor finding thine own pleasure, nor speaking thine own words:
Then shalt thou delight thyself in the LORD; and I will cause thee to ride upon the high places of the earth, and feed thee with the heritage of Jacob thy father: for the mouth of the LORD hath spoken it.
Isaiah 58:13-14 KJV
Conclusion
To conclude, yes, it is a sin to not keep the Sabbath. God wants obedience from us, and if we love Him for what He did for us, we need to obey Him and His commandments. (John 14:15)
The Sabbath is not a burden, but a day when we lay aside all the stress, problems, and day-to-day issues of life.
We take time to reconnect with our Creator and to know Him better.
He is the Only One who can help us with all our problems, and who loves us beyond our imagination.
He gave His Son to die on the cross for our sins, so that we may live.
Let us not disappoint Him and the great sacrifice that was made for our salvation.
Let us keep all of His commandments, not only 9 of them, for it is written:
Blessed are they that do his commandments, that they may have right to the tree of life, and may enter in through the gates into the city.
Revelation 22:14 KJV
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