The word translated "sin" in the Bible means to miss the mark. The mark for humans was to be the "image of God", but all humanity falls short of that mark. They are estranged from God as the result, and stand in need of salvation, reconciliation, and transformation..
"...for all sinned and are wanting of the glory of God." (Romans 3:23)
"...the ration for sin is death, yet the gracious gift of God is life eonian, in Christ Jesus, our Lord." (Romans 6:23)
God's plan for saving humanity from death involves "bloodshedding" to cleanse - but the blood must come from an innocent source.
"And almost all is being cleansed in blood according to the law, and apart from bloodshedding is coming no pardon." (Hebrews 9:22)
The blood of ordinary human beings or animals could not atone for sin. This was clearly shown in the history of Israel. The bloody sacrifices of animals was only a "shadow" of the permanent cleansing that God the Father would provide by the "gracious gift" of His Son.
"For the law, having a shadow of the impending good things...with their same sacrifices which they are offering year by year, are never able to perfect to a finality...in them there is a recollection of sins year by year; for it is impossible for the blood of bulls and of he-goats to be eliminating sins." (Hebrews 10:1-4)
The blood of Jesus, an innocent human was sacrificed once and for all humanity. It took "away the sin of the world". Jesus, the original Son of God, saved humanity from perishing in death, and reconciled the world to God the Father.
"On the morrow he is observing Jesus coming toward him, and is saying, Lo! the Lamb of God which is taking away the sin of the world." (John 1:29)
"...yet now, once, at the conclusion of the eons, for the repudiation of sins through His sacrifice, He is manifest." (Hebrews 9:26)
Jesus always did the will of His Father, and it was the Father's will for Him to shed His "blood" to take away the sins of the world and bring reconciliation to the entire creation.
"My little children, these things I am writing to you that you may not be sinning. And if anyone should be sinning, we have an Entreater with the Father, Jesus Christ, the Just. And He is the propitiatory shelter concerned with our sins, yet not concerned with ours only, but concerned with the whole world also." (1 John 2:1-2)
"God is commending this love of His to us, seeing that, while we are still sinners, Christ died for our sakes." (Romans 5:8)
"God was in Christ, conciliating the world to Himself, not reckoning their offenses to them...For the One not knowing sin, He makes to be a sin offering for our sakes that we may becoming God's righteousness in Him." (2 Corinthians 5:18-21)
God the Father sacrificed His one and only begotten Son for our sake.
"This one, given up in the specific counsel and foreknowledge of God, you, gibbeting by the hand of the lawless, assassinate...Yet what God announces before through the mouth of all the prophets - the suffering of His Christ - He thus fulfills." (Acts 2:23; 4:18-19)
The "love" of God did this for all "irreverent" sinners, not just a few.
"For Christ, while we are still infirm, still in accord with the era, for the sake of the irreverent, died" (Romans 5:6-7)
"Yet now, in Christ Jesus, you, who were once far off, are become near by the blood of Christ." (Ephesians 2:13)
God is "for us" sinners, not against us as some suggest, so we need not worry about the future of humanity.
If God is for us, who is against us? Surely He who spares not His own Son, but gives Him up for us all, how shall He not, together with Him, also, be graciously granting us all?" (Romans 8:31-32)
Do not let the religious doctrines of men rob you of the truth of God's great love for all humanity, and rob you of the knowledge that His plan is to save and reconcile humanity to Himself in His "grace" through the "blood" of our Lord Jesus Christ.
"Blessed be the God and Father of our Lord Jesus Christ, Who blesses us with every spiritual blessing among the celestials, in Christ, according as He chooses us in Him before the disruption of the world, we to be holy and flawless in His sight, in love, designating us beforehand for the place of a son for Him through Christ Jesus; in accord with the delight of His will, for the laud of the glory of His grace, which graces us in the Beloved."
(Ephesians 1:3-6)
Yes, that is the glorious plan of God the Father!
"...in Whom we are having the deliverance through His blood, the forgiveness of offenses in accord with the riches of his grace, which He lavishes on us.; in all wisdom and prudence making known to us the secret of His will." (Ephesians 1:7)
The salvation of humanity is no longer a secret to those who believe the Bible.
"And the Word became flesh and tabernacles among us, and we gaze at His glory as of an only-begotten from the Father, full of grace and truth. John is testifying concerning Him and has cried, saying, 'this was He of Whom I said, He Who is coming after me, has come to be in front of me, for He was first before me, for of that which fills Him we all obtained, and grace for grace. For the law through Moses was given; grace and truth came through Jesus Christ. God no one has ever seen. The only-begotten God, Who is in the bosom of the Father, He unfolds Him." (John 1:14-18)
Finally, our Lord Jesus will transform all of us out of our mortal sinful bodies into an immoral spiritual body and we will become eternal citizens of the Kingdom of God.
"But our citizenship is in heaven, and we eagerly await a Savior from there, the Lord Jesus Christ, who, by the power that enables Him to subject all things to Himself, will transform our lowly bodies to be like His glorious body." (Philippians 3:20)
"Beloved, we are now children of God, and what we will be has not yet been revealed. We know that when Christ appears, we will be like Him, for we will see Him as He is." (1 John 3:2)