Hebrews 12:1 says,
"Therefore, since we are surrounded by such a great cloud of witnesses, let us throw off everything that hinders and the sin that so easily entangles."
Hebrews 11 contains a list of Jewish people from the Old Testament who lived by faith.
They are the great cloud of witnesses that “we” (the Jewish-Hebrew people) were surrounded by, serving as an example to them of those who lived by faith.
The reason Hebrews 11 exists, the chapter on faith, was to prove to the Jewish people that living by faith was not a foreign way of life for Jewish people.
Living by faith was in their roots.
The book of Hebrews was written to Jewish people to convince them to leave behind - "throw off" - the dead works of the old covenant of law.
The writer of Hebrews was exhorting the Hebrew people to rest in the new covenant of grace live by faith in Jesus.
The law was hindering them...keeping them from faith in Jesus.
Living in the new covenant of grace was living by faith in Jesus as the full, final, and forever sacrifice for sin.
In the new covenant, all sins for all time are forgiven.
God remembers sins no more.
There is no more sacrifice for sins because Jesus was the full, final, and forever sacrifice.
There was no more forgiveness needed.
To access what Jesus did by grace (Hebrews 2:9), faith in him was required.
Faith receives what Jesus achieved by grace.
This life of faith in Jesus was demonstrated by leaving behind - "throwing off" the rules, rituals, and requirements (works) of the old covenant.
However, most of the Jewish people would not throw off the Law of Moses (works) and live by faith in Jesus (grace).
They had sinful, unbelieving hearts (Hebrews 3:12) that continued to live by the works of the Law of Moses, the old covenant.
The concept of faith alone in Jesus alone minus works was not comfortable for them, nor was it enough for them.
They wanted to either live by the law or live by a combination of the law (works) and Jesus (grace).
They were very uncomfortable with faith alone.
Therefore, the writer of Hebrews proves from their ancestral history that living by faith is a part of their heritage (Hebrews 11).
Those of Hebrews 11 served as an example of living by faith to the generation the writer of Hebrews wrote to so he could convince them to enter into and rest in the new covenant of grace through faith in Jesus (Hebrews 3-4).
He was trying to convince them to live by faith in Jesus and not by the works of the Law of Moses.
The sin that so easily entangles is the sin of unbelief, which is rejecting the new covenant of grace established by the blood of Jesus and then seeking to make ourselves righteous, holy (clean and pure before God), and forgiven through works of the law – or through any personal effort where one is dedicated to a set of disciplines to follow, such as a moral, spiritual, or religious system, thinking these efforts will result in right standing with God.
The Jews sinned through unbelief by continually seeking holiness before God and forgiveness from God by following the rules, rituals, and requirements of the law.
Why is seeking a holy standing before God and forgiveness from God by the law (or any personal, spiritual, or religious effort) the sin that so EASILY entangles?
People are easily entangled because the fallen nature of mankind wants to earn a holy, righteous, and forgiven standing before God.
It feels good to the flesh to earn something.
They want to contribute to staying forgiven and in fellowship (close to) God.
Therefore, they remain in unbelief that Jesus alone secured a righteous, holy, and forgiven standing before God by grace, through his blood, on their behalf.
No person can make himself holy, righteous, or forgiven through works of the law, moral living, or spiritual and religious acts.
Only Jesus, by his grace and through his blood, can make us righteous, holy, and forgiven.
To reject Jesus as the full, final, and forever sacrifice for sin…to reject his blood as the only way we can experience a righteous, holy, and forgiven standing before God is the sin that so easily tangles.
To put forth effort to stay forgiven and in fellowship with God through a religious system or set of spiritual disciplines is the sin that so easily tangles.
To fail to rest by faith in Jesus and his blood to make us righteous, holy, and forgiven by God is the sin that so easily entangles.
It is the sin of unbelief.
It is the sin many of the Jewish people committed when the book of Hebrews was written and it is the same sin many leaders and members of the church families commit today.
Rather than resting by faith in the full, final, and forever payment for their sins by Jesus…rather than resting in his blood alone for a righteous, holy, and forgiven standing before God, they try to make themselves righteous, holy, and forgiven through spiritual, religious, or personal effort.
And that is the sin which so easily entangles.