(1) "Jesus has freed us/bought us from sin by sacrificing his pure human life. The Devil can't claim us anymore, like he could do before."
(??) But we aren't really free from sin now, are we? I mean, we are still tempted to do sinful things.
Satan was not “paid off” by Christ going to the cross. God does not owe satan anything and can certainly easily and safely take away from satan anything.
Jesus is not taking our free will away from us, so even as Christians we can still quench the Spirit and sin.
Read more below to find out what really is happening.
(2) "Jesus has fulfilled the law, embodied it and has therefore freed us from it."
(??) But Jesus said that the law is still every bit as important as it used to be, right? So what changed in our relationship with the law if we still need to follow it?
In some ways there are even more “rules” we get to obey.
Trying to follow the “Law” to earn our salvation is just not possible, so we need a remedy for sinning, but the Law does not provide a remedy for rebellious disobedience other that banishment or death and we are all guilty of these types of sin. The answer to this gets really wordy since it has to do with understanding atonement. I also read the rest of your questions which stem from a misunderstanding of atonement, which many teach unfortunately. I will skip to an explanation of atonement and we can go back afterwards if you feel it does not address your questions.
(3) "Jesus has built the ultimate bridge between humanity and God. Now each of us can have a personal relationship with God."
(??) But does that mean that a relationship with God was impossible before Jesus' death? Abraham, Jacob, Moses and tons of other people had contact with God, right? Also, Buddha for example was a highly spiritual person, so I suppose the Holy Spirit also flowed through him, right? So if prayer, divine inspiration and contact with God were all possible before the Cross, then what really changed in our relationship with God? What got bridged?
(4) "Jesus has freed all the people from purgatory and brought us the option to go to heaven." (I'm really not clear on this one)
(??) Yeah, I don't get the implications of Jesus' death and resurrection to the afterlife at all. So hell kind of existed before, but purgatory doesn't anymore? But people can still go to
hell, so we're not free, right? Also, was there a heaven for us people to go to before Jesus?
(last question) So my last question would be, what were the practical differences for a person before and after the cross? What really changed inside and outside of every person 2000 years ago? For example, what changed in the aboriginal people at that time? Were they also able to feel the planetary change that Jesus had ushered in?
Thank you so much for reading and answering my question. It really helps my development in Faith. If you guys could, I would really like you all to keep your answers as practical, simple and non-cryptic as possible. Thank you all

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Greats, Kees.
We can work on this together and draw our own most likely alternative interpretation that will be very biblical, consistent and logical.
To begin with:
During the time of Christ, the Jewish people in and around Jerusalem would have had a much better understanding of atonement since atonement sacrifices were going on every hour at the temple, maybe thousands each day. All mature adults would have most likely participated in the individual process of atonement, but this was only for unintentional sins (really minor sins) since intentional sins had no Old Testament system for atonement.
Those only able to afford a bag of flour (Lev. 5) certainly would not have considered that bag of flour to be a “substitute” for them. There is nothing to suggest the Jewish people ever thought of any sacrifices to be substitutes for them. So what did they experience in this atonement process for unintentional sins?
If we could relate to their atonement experience for “minor” sins we might be able to extrapolate to what the atonement process would be like for intentional sins? (Read Lev. 5)
Forgiveness for unintentional sins came after the completion of the atonement process (Lev. 5), but did God need a bag of flour to forgive the person’s sins?
Would God need anything to forgive a person’s sins or is it the person needing something to accept that forgiveness as pure charity?
Christ Crucified is described by Paul, Peter, Jesus, John and the Hebrew writer as a literal ransom payment (it is not even said to be like a ransom payment, but it was a ransom payment)?
I find the ransom description more than just an analogy to be an excellent fit and I am not talking about the “Ransom Theory of Atonement”
(The “Ransom Theory of Atonement” has God paying satan the cruel torture, humiliation and murder of Christ but: Does God owe Satan anything? Is there some cosmic “law” saying you have to pay the kidnapper? Would it not be wrong for God to pay satan, if God could just as easily and safely take back His children without paying satan?)
Would a ransom as those in the first century might understand it (it was well known Caesura at 21 had been kidnapped and a ransom paid for him) included the following elements:
1. Someone other than the captive paying the ransom.
2. The payment is a huge sacrificial payment for the payer, who would personally prefer not to pay.
3. Since those that come to God must come as children, it is the children of God that go to the Father.
4. The payer cannot safely or for some other reason get his children by any other way than making the payment.
5. The kidnapper is totally undeserving.
6. The kidnapper can accept or reject the payment.
Go to Luke 15: 11-32 the prodigal son story to illustrate:
Who in the middle of the night snuck in and dragged off the young son, force the son to do evil stuff and finally chained him to a pigsty starving to death? (this is not the way it happened, but the child of the father was kidnapped.)
Who returned to the father, was it the son that rebelliously wished his father’s death so he could get his inheritance or was it the child of the father?
We can only come to our Father as children, so who is keeping the nonbeliever in the unbelieving state (who is this kidnapper)?
There is the one ransom, but could there be many kidnappers and many children?
Who are the kidnappers?
Looking at verses in particular:
(NIV) Ro. 3:25 God presented Christ as a sacrifice of atonement, through the shedding of his blood—to be received by faith. He did this to demonstrate his righteousness, because in his forbearance he had left the sins committed beforehand unpunished—
“God presented” this might be better expressed as “God is offering” since it will later be received, received or rejected on the contingency of some kind of “faith”. Instead of “received” it might better be translated as accepted (with the option of being rejected or not accepted).
“Sacrifice of atonement” is described by Jesus, Paul, Peter, John and the Hebrew writer as the “ransom payment” or just “ransom”. So God is offering a ransom payment to be accepted by those with faith or rejected by those refusing or just not accepted by those lacking faith.
A huge part of that ransom payment that especially applies to those that are already Christians is the life giving cleansing blood of Christ. Christ and God would have personally preferred that blood remained in Christ’s veins, but I needed it given up by Christ to flow over both my outside and my heart to know, experience, “trust” and feel I am cleansed and made alive. So Christ willingly gave up His blood for me and because of me. This is an overwhelming tragedy I insisted on to believe: I was made holy, righteous and stand justified. Without knowing and feeling this blood flowing over my heart, I might question my cleansing?
“Demonstrate his righteousness” God did not become righteous, but just showed the righteousness He has always had. (God’s justice/ holiness/being right) comes with the atoning sacrifice that includes the life giving cleansing blood showing God’s righteousness/justice in a very particular way; by resolving the huge problem that existed under the Old Covenant. That huge problem in the Old Covenant was with the handling of intentional sins that where committed, repented of, and which the individual sought forgiveness from God for doing (and God forgave without justly disciplining the sinner [thus not showing His righteousness through His disciplining]). These sins could be forgiven by God, but there was no way to fairly/justly discipline (punish) the sinner and still have the sinner live in the Promised Land. God did have fair/just punishments (discipline) for these sins, but the Jews could not follow through with them, since all Jews deserved to be treated similarly (there would be no one left in the Promised Land).
“in his forbearance he had left the sins committed beforehand unpunished” Instead of “unpunished” I would translate that Greek word to be “undisciplined”.
“because in his forbearance he had left the sins committed beforehand unpunished”, shows the contrast between before and after the cross. This is not saying: “before the cross sins are now being punished by Christ going to the cross”, but is saying they were left unpunished prior to the cross. If they are being handled the “same way” as sins after the cross there would be no contrast? (And there are lots of other problems with this reasoning.) There is no “punishment” (disciplining for intentional sins) before the cross yet there is “punishment” (disciplining of God’s children) with the cross.
Any good parent realizes the need for not just forgiving their rebellious disobedient child, but to also see to the child’s fair/just/loving discipline if at all possible, but under the Old Covenant there was no “fair/just/loving discipline” so God could not show His justice/righteousness except to point out in the Law what really should happen, but that is not “good” disciplining, the child can almost feel they got away with something.
By my coming to the realization of my forcing Christ to be tortured, humiliated and murdered, because of my personal sins I experience a death blow to my heart (Acts 2: 37) the worst possible experience I can have and still live (That is also the most sever disciplining I can experience and still live). Thus I know God is my loving concerned Parent (since He at great cost has seen to my disciplining). I know how significant my sins really are; I can put those sins behind me after being disciplined. Since God and Jesus shared in my disciplining “I am crucified with Christ” (a teaching moment) our relationship is even greater than before my transgressing.
What is the benefit/value for us that we would want to accept the ransom payment of Christ’s torture, humiliation and murder?
What value benefit did it have for those 3000 on the day of Pentecost?
Would those 3000 have become baptized believers on the day of Pentecost if Peter had not been able to say: Acts 2:36 “…this Jesus whom you crucified”?
So for those 3000, their crucifying Christ (ransom payment/atoning sacrifice) resulted in them becoming baptized believers on the day of Pentecost! Did it have value for them?
This will get us started if you really want to know.