Can One’s Salvation Be Given Up?

Indeed he could have, but under the Law of Moses which was still valid then, they had to be circumcised and follow the Law to do so.
Exodus 12:48, and Acts 15:1

An easier explanation would be that Jesus commanded Peter not to preach the gospel of the kingdom to the Gentiles (Matthew 10:5)

It really baffles me that you think the gospel Paul taught (how Christ died for our sins and was resurrected) is the same gospel that the disciples taught (the gospel of the kingdom). And yet, I showed you many scriptures where the disciples had no clue of Christ’s d,b,r for sins. It was hid from them on purpose. Why was it hid?

1 Corinthians 2 (Paul)
6 Howbeit we speak wisdom among them that are perfect: yet not the wisdom of this world, nor of the princes of this world, that come to nought:
7 But we speak the wisdom of God in a mystery, even the hidden wisdom, which God ordained before the world unto our glory:
8 Which none of the princes of this world knew: for had they known it, they would not have crucified the Lord of glory.

The cross had to be hidden from man. If Satan knew the outcome of the cross, he would have never initiated it to happen. He thought he was gaining the victory by having Jesus killed.

He still believes the gospel of the kingdom is how Christ died for our sins, was buried and resurrected the third day.

No, I'm not saying they preached the death and resurrection of Christ.

17I will rescue you from your own people and from the Gentiles. I am sending you to them 18to open their eyes and turn them from darkness to light, and from the power of Satan to God, so that they may receive forgiveness of sins and a place among those who are sanctified by faith in me.’

19“So then, King Agrippa, I was not disobedient to the vision from heaven. 20First to those in Damascus, then to those in Jerusalem and in all Judea, and then to the Gentiles, I preached that they should repent and turn to God and demonstrate their repentance by their deeds.

It's the same message, but now with the sacrifice of Christ as the specific object of faith in God and the power of that salvation.

Not including Christ by name, of course.
That goes without saying.

Very true. You will hear all sorts of theologies and usually everyone has the true interpretation lol. I'm guilty though. To me my current interpretation is true. It may get tweaked but ultimately in my opinion we make the Gospel way more complicated than it needs to be.

Not much has influenced my overall interpretation from just plainly reading the Bible from cover to cover. All the study and research has added details but nothing really affected the core message. If the Bible was all we had without the commentary, bible studies, scholars etc. We would still be perfectly equipped to be saved and to preach the Word.

That is the result of anticipating revelation, inserting Paul into the 4 Gospels and early Acts.

There is a difference between saying:

1. Jesus died because you murdered him, and rose again because he is the Son of God, the grave could not hold him (Acts 2:24-36), VERSUS
2. Jesus died for your sinful nature you inherited from Adam (Romans 5:12-19), and rose again as a sign that you are now righteous before God. (2 Cor 5:21)

It’s nothing against you. I just find it to a case of erroneous theology.

I really think you're making this way to complicated.

Go all the way back to God's promise to Abraham and work your way forward.
It's always been about God's promise to Abraham about a son.
That's where the gospel starts.
Same message, additional details.

(Yes, I know, we see hints of the gospel in the garden.)

Okay, if you insist its the same, I can understand why you do.

Fortunately, all of us are saved by Paul's gospel of grace so for people who want to hold the doctrine that the Jews had exactly the same gospel then, even though the bible call that the gospel of the kingdom, its okay, we can agree to disagree there.

The Bible also said the Angel Gabriel called Ezekiel the Son of Man. It’s all about the context.

So would you agree with this statement?

Do you adhere to Pauline theology (also called Paulism or Paulanity the Gentile Christianity? And support this idea, "Paul's writings contain teachings that are different from the original teachings of Jesus, the earliest Jewish Christians, as documented in the canonical gospels, and early Acts?

Yes, scripture itself stated it clearly, that the revelations Paul received was something that was new, new enough that made apostle Peter, for example, remarked that he found it difficult to understand too.

We call this the mystery, that God had hidden since the foundations of the world began, and only revealed that to Paul after he was saved.

Is that belief really that heretical to you?

Thank you. I cannot make a judgment if this theology is heretical until I understand what are you denying from the 4 eyewitness accounts and early acts?

Many of you would deny this, for example, even though Jesus did mentioned it in the 4 eyewitness account. That is the problem of not rightly dividing the word of truth.

https://christianchat.com/threads/not-by-works.146296/post-4148476

You are correct with understanding who Jesus was talking to, time period, culture, place and topic. All can provide us with clarity.

No Jesus wasn't promoting a legalistic system but was in fact providing a clear example of the law and how more than likely anyone who heard the Beatitudes saw their own imperfections. Which is the main idea behind most of Jesus's teachings. The law was Holy and perfect so by us taking what Jesus said in the Beatitudes and applying it to our lives, we would be acting from love as Jesus said if you love me you will keep my commands.

Jesus made a hard push to show the hypocrisy of the day by providing countless examples of how people just didn't measure up. The whole idea was to get them to understand the true role of the Messiah.

Matthew 5:17-20 New International Version (NIV)
The Fulfillment of the Law
17 “Do not think that I have come to abolish the Law or the Prophets; I have not come to abolish them but to fulfill them. 18 For truly I tell you, until heaven and earth disappear, not the smallest letter, not the least stroke of a pen, will by any means disappear from the Law until everything is accomplished. 19 Therefore anyone who sets aside one of the least of these commands and teaches others accordingly will be called least in the kingdom of heaven, but whoever practices and teaches these commands will be called great in the kingdom of heaven. 20 For I tell you that unless your righteousness surpasses that of the Pharisees and the teachers of the law, you will certainly not enter the kingdom of heaven.

Of course the Gentiles at first wasn't the main focus even though it had been prophesied and Jesus did in fact have many different occasions with Gentiles including 1 who he said had the greatest of faith. Or the woman at the well who he told to believe in him. When Peter first preached after receiving the Spirit, he was preaching to people from all over the known world including Gentiles. Many came to faith.

Paul was obviously more of a scholarly man so of course his teachings was often deeper and even hard for scholars today to agree on. But that doesn't prove anything. Paul and the Disciples taught the same Gospel. Paul was sent more to the Gentiles while the disciples mainly focused on the Jews but also spread out to the gentile world.