We can stay in Acts 15 and solve this whole debate. The entire premise of the Council of Jerusalem was that Torah observance was the accepted norm. What was being decided was whether or not there was an alternative that would mot be a roadblock for gentiles. There was never even a question of whether Peter or James or any of the rest of them would continue to follow Torah. It was explicit that they would and even that the Gentiles would have a path to observe it too. The statement explicitly references the continued access of gentile believers to Moses and the prophets. Paul happily agreed with this statement. I am flummoxed at any claim to the contrary.
Acts 15. The issue is clear:
"5 Then some of the believers who belonged to the party of the Pharisees stood up and said, “The Gentiles must be circumcised and required to keep the law of Moses.”
Peter:
"10 Now then, why do you try to test God by putting on the necks of Gentiles a yoke that neither we nor our ancestors have been able to bear? 11 No! We believe it is through the grace of our Lord Jesus that we are saved, just as they are.”
James:
“19 It is my judgment, therefore, that we should not make it difficult for the Gentiles who are turning to God."
The action item turned into a letter which I quote in full:
"The apostles and elders, your brothers,
To the Gentile believers in Antioch, Syria and Cilicia:
Greetings.
24 We have heard that some went out from us without our authorization and disturbed you, troubling your minds by what they said. 25 So we all agreed to choose some men and send them to you with our dear friends Barnabas and Paul— 26 men who have risked their lives for the name of our Lord Jesus Christ. 27 Therefore we are sending Judas and Silas to confirm by word of mouth what we are writing. 28 It seemed good to the Holy Spirit and to us not to burden you with anything beyond the following requirements: 29 You are to abstain from food sacrificed to idols, from blood, from the meat of strangled animals and from sexual immorality. You will do well to avoid these things.
Farewell."
So I get that the answer to the question "Should the Gentiles be circumcised and required to keep the law of Moses.” is a resounding no. Some friendly advice, yes. But no circumcision and no requirement to keep the law of Moses. And it is not just a Paul thing. Peter and James are onboard, too. Indeed it is the official position of the Apostles as a whole.
I am flumoxed that you see the answer as a reply for Gentiles to be circumcised and to keep the law of Moses. It is nowhere in the letter and seems 180 degrees wrong. That would be going directly against verses 10 and 19.
I should also note that according to the letter the people who were preaching verse 5 "went out from us without our [the apostles] authorization" and "disturbed you" and were "troubling your minds". This letter is clearly not an endorsement of the position in verse 5. Clearly it IS an endorsement of Paul who is referred to as a "dear friend" in verse 25 and we all know his position on the issue. He is the guy who is strongly opposed to the position in verse 5.