Hebrews 12:1 Therefore we also, since we are surrounded by so great a cloud of witnesses, let us lay aside every weight, and the sin which so easily
ensnares us, and let us run with endurance the race that is set before us.
Hebrews 12:1 is speaking on outside influence, it refers to external pressure, not active personal sin. The author does not say that the believer falls into sin, but that the influence of sin is all around him and seeks to reach him as it says in Genesis 4:7. He is highlighting the sin that surrounds and attacks believers, that is, the outside influences that seek to cause them to fall.
“The sin which so easily ensnares us” In a world filled with corruption and iniquity, the outside pressure of sin is omnipresent. The temptations, evil influences, and seductions of the world are constantly trying to weaken the
believers and to turn them away from their call to holiness. Hebrews 12:14.
Ephesians 6:12 For we wrestle not against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this world,
against spiritual wickedness in high places. “lay aside” means to refuse anything that would turn us away from the pure and victorious race of the Christian, a call to guard against spiritual dangers that come from the outside
environment.
This exhortation applies to everyone to remain vigilant against external attacks
The author of Hebrews often uses “we” as a collective writing style to speak to believers, but this does not mean that he includes himself in the category concerned.
This spoken figure of speech also exists in Paul, John and James, who use “we”
to express general principles without necessarily including
themselves.
He is addressing a mixed assembly, just as Paul in Romans
13:12, James 3:9 and John in 1 John 1:8, which includes new converts, enlightened believers not fully regenerated, little children in the faith, as well as spiritual youth and mature adults in holiness.
So, Hebrews 12:1 does not prove that believers still struggle with personal sin, but warns against the pressures of the sinful world that seek to disturb their walk with God. The call to reject sin is an exhortation to protect ourselves from these destructive influences and to press on with perseverance toward spiritual perfection.