In large part, yes, I agree with that.
The question is, what are they misunderstanding?
Most equate salvation in the Old Testament with salvation in Christ in the New Testament. That is the fundamental error of most, and it is bred by failure to address these issues directly.
If you think Peter was saved, let me ask you this...can one be saved (in a New Covenant sense) and not believe the Lord has risen? That is true of all the disciples:
Mark 16:9-14
King James Version (KJV)
9 Now when Jesus was risen early the first day of the week, he appeared first to Mary Magdalene, out of whom he had cast seven devils.
10 And she went and told them that had been with him, as they mourned and wept.
11 And they, when they had heard that he was alive, and had been seen of her, believed not.
12 After that he appeared in another form unto two of them, as they walked, and went into the country.
13 And they went and told it unto the residue: neither believed they them.
14 Afterward he appeared unto the eleven as they sat at meat, and upbraided them with their unbelief and hardness of heart, because they believed not them which had seen him after he was risen.
You probably have never given this much thought, but, if you consult all of the Gospels you will see this in each.
The problem was that the Gospel of Jesus Christ was not revealed to them yet. They were told, true, and had the Gospel of Christ in Prophecy, but, they had not the understanding:
John 20:9
King James Version (KJV)
9 For as yet they knew not the scripture, that he must rise again from the dead.
No, Jason, the New Covenant is not the exact same deal.
The Covenant of Law did not have remission of sins on an eternal basis. It did not have the Eternal Indwelling of GOd, It did not have Christ our Great High Priest. It did not offer Reconciliation to God.
Men were justified by faith, to be sure, but let's not equate that with being Justified by the Blood of Christ:
Romans 3:20-26
King James Version (KJV)
20 Therefore by the deeds of the law there shall no flesh be justified in his sight: for by the law is the knowledge of sin.
21 But now the righteousness of God without the law is manifested, being witnessed by the law and the prophets;
22 Even the righteousness of God which is by faith of Jesus Christ unto all and upon all them that believe: for there is no difference:
23 For all have sinned, and come short of the glory of God;
24 Being justified freely by his grace through the redemption that is in Christ Jesus:
25 Whom God hath set forth to be a propitiation through faith in his blood, to declare his righteousness for the remission of sins that are past, through the forbearance of God;
26 To declare, I say, at this time his righteousness: that he might be just, and the justifier of him which believeth in Jesus.
Abraham is said to be justified by both works and faith, and this is true, but, we can't have the Justification which is through the Blood (Death) of Christ...before His death.
Scripture doesn't teach that, neither should we.
And note v.25 is saying the exact same thing Hebrews 9:15 states, that is, that the sins of the Old Testament Saint were overcome by the Righteousness of Christ, through His Blood (Death, Offering of Himself).
As we saw earlier, "The Law could not make perfect because the blood of bulls and goats cannot take away sins." Hebrews 10:1 & 4.
However...
Hebrews 10:14
King James Version (KJV)
14 For by one offering he hath perfected for ever them that are sanctified.
That is the promise of God...
Hebrews 8:12
King James Version (KJV)
12 For I will be merciful to their unrighteousness, and their sins and their iniquities will I remember no more.
...found in the very Promise of the New Covenant.
Continued...