Then Paul was not the first.
Yes, he was and 1 Timothy 1:16 KJV tells us why!
1 Timothy 1:16 Howbeit for this cause I obtained mercy, that in me first Jesus Christ might shew forth all longsuffering, for a pattern to them which should hereafter believe on him to life everlasting.
Peter was the first to preach the gospel of salvation to the Gentiles.
Act 15:7 And when there had been much disputing, Peter rose up, and said unto them, Men and brethren, ye know how that a good while ago God made choice among us, that the Gentiles by my mouth should hear the word of the gospel, and believe.
Act 15:8 And God, which knoweth the hearts, bare them witness, giving them the Holy Ghost, even as he did unto us;
Act 15:9 And put no difference between us and them, purifying their hearts by faith.
Act 15:10 Now therefore why tempt ye God, to put a yoke upon the neck of the disciples, which neither our fathers nor we were able to bear?
Act 15:11 But we believe that through the grace of the Lord Jesus Christ we shall be saved, even as they.
Peter preached a different gospel entirely to those Gentiles Acts 10:35 KJV than that which Paul preached Titus 3:5 KJV! The gospel of Christ cannot be found in Acts 10!
You believe the sins of the 3000 were not washed away, but that they will be in the future.
Falsehood
Rom 5:9 Much more then, being now justified by his blood, we shall be saved from wrath through him.
Rom 5:10 For if, when we were enemies, we were reconciled to God by the death of his Son, much more, being reconciled, we shall be saved by his life.
Rom 5:11 And not only so, but we also joy in God through our Lord Jesus Christ, by whom we have now received the atonement.
LA
In typical wrongly dividing style, LA wishes to make mush out of the word of God.
Those of Pentecost will have their sins blotted out when the times of refreshing comes from the presence of the Lord! It is written:
Acts 3:19 Repent ye therefore, and be converted, that your sins may be blotted out, when the times of refreshing shall come from the presence of the Lord;
Acts 3:20 And he shall send Jesus Christ, which before was preached unto you:
Acts 3:21 Whom the heaven must receive until the times of restitution of all things, which God hath spoken by the mouth of all his holy prophets since the world began.
Acts 3:22 For Moses truly said unto the fathers, A prophet shall the Lord your God raise up unto you of your brethren, like unto me; him shall ye hear in all things whatsoever he shall say unto you.
Paul even confirms it!
Romans 11:26 And so all Israel shall be saved: as it is written, There shall come out of Sion the Deliverer, and shall turn away ungodliness from Jacob:
Romans 11:27 For this is my covenant unto them, when I shall take away their sins.
You do not get to apply Romand 5 to Israel as Israel will absolutely go through wrath!
1 Peter 1:7 That the trial of your faith, being much more precious than of gold that perisheth, though it be tried with fire, might be found unto praise and honour and glory at the appearing of Jesus Christ:
1 Peter 1:8 Whom having not seen, ye love; in whom, though now ye see him not, yet believing, ye rejoice with joy unspeakable and full of glory:
1 Peter 1:9 Receiving the end of your faith, even the salvation of your souls.
Not so with us members of the Body of Christ!
Romans 5:9 Much more then, being now justified by his blood, we shall be saved from wrath through him.
1 Thessalonians 5:9 For God hath not appointed us to wrath, but to obtain salvation by our Lord Jesus Christ,
You simply do NOT have your facts straight. It's natural for you 1 Corinthians 2:14 KJV.