Well, let me ask it this way. What are Peter and the 11 promised by Christ that they will be doing when He returns and sets up His Kingdom on earth?
"And Jesus said unto them, Verily I say unto you, That ye which have followed me, in the regeneration when the Son of man shall sit in the throne of his glory, YE ALSO SHALL SIT UPON TWELVE THRONES, JUDGING THE TWELVE TRIBES OF ISRAEL." Mat. 19:28.
So, Peter and the 11 were to go to all nations, preaching the kingdom gospel to all people, but when Christ returns to set up His kingdom, they will be judging the 12 tribes of Israel. Does that make any sense? The only way it makes sense is IF Israel HAD ACCEPTED CHRIST as their Messiah, THEN the 12 would have gone to all nations, preaching the gospel of the kingdom, Christ would have returned, set up His Kingdom, and Israel would have become a nation of priests and a blessing to all nations. But we know that Israel REJECTED Christ. And they were blinded, set aside, became Lo Ammi, and the Kingdom is now in abeyance, until the fulness of the Gentiles be brought in. Which is where Paul enters. And the Church the Body of Christ. And the gospel of the grace of God.
If Christ promised them in Mat. 19:28 that they would be judging the 12 tribes of Israel during the Millineal reign, and IF Christ told them to "go NOT into the way of the Gentiles" (10:5), and IF Christ emphasizes in 15:24 that He was sent to Israel- "But he answered and said, I am not sent but unto the lost sheep of the house of Israel", then what would common sense tell you they believed? NOT to go to the Gentiles with any kingdom gospel until those they are going to judge one day (Israel) is FIRST brought to belief.
Mark, you're giving me tradition as proof they went outside Israel. That is not what the Bible says. They did EXACTLY as commanded BY CHRIST.
2 Peter 3 says what they ought to be doing.
11 Since everything will be destroyed in this way, what kind of people ought you to be? You ought to live holy and godly lives 12 as you look forward to the day of God and speed its coming.[b] That day will bring about the destruction of the heavens by fire, and the elements will melt in the heat. 13 But in keeping with his promise we are looking forward to a new heaven and a new earth, where righteousness dwells. 14 So then, dear friends, since you are looking forward to this, make every effort to be found spotless, blameless and at peace with him. 15 Bear in mind that our Lord’s patience means salvation, just as our dear brother Paul also wrote you with the wisdom that God gave him. 16 He writes the same way in all his letters, speaking in them of these matters. His letters contain some things that are hard to understand, which ignorant and unstable people distort, as they do the other Scriptures, to their own destruction. 17 Therefore, dear friends, since you have been forewarned, be on your guard so that you may not be carried away by the error of the lawless and fall from your secure position. 18 But grow in the grace and knowledge of our Lord and Savior Jesus Christ. To him be glory both now and forever! Amen.
Oh dear, sounds like Peter is accusing Paul of teaching a salvation that can be lost by evil works...