Acts 15 specifically declares that nothing should be required of the Gentiles but four laws, three of them related to blood.
In the same way that an employer doesn't want to make things too difficult for a new employee by requiring them to learn everything they will ever need to know about how to do their job up front, then goal in Acts 15:19-21 was not to make things too difficult for new Gentile believers coming to Christ. The four laws were a starting point that would allow them to have fellowship with the Jews as they continued to learn about how to obey God. It was intended for new believers, not mature ones. Acts 15:21 indicates that they would continue to learn about how to keep the law every Sabbath, otherwise what was his point in adding afterward?
Galatians 5 warns Gentiles not to receive circumcision or they will be required to keep the whole Torah. The clear implication here is that without circumcision, Gentiles are not required to keep the whole Torah.
The problem with the Galatians is that they were already justified by faith, but they were starting to listen to those that were saying that they had to keep the law in the way that the Jews did in order to be saved. If they were going to reject Christ's gift and try to become justified through their own effort, then they would need to keep the whole law in order to be justified. This implies nothing about whether Gentiles are required to obey the law for reasons other than justification.
Colossians 2 warns that no one is to judge the Colossians with regard to Sabbath, New Moons or festivals. These are a shadow; the substance is Messiah.
Paul would not use the words in Colossians 2:8 to describe God's holy, righteous, and good law, but rather as Colossians 2:20-23 details, he was speaking against human traditions and self-made religion and asceticism and severity to the body. So the Colossians were not being judged for not keeping God's Sabbaths, but because they were keeping them, and Paul was encouraging them not to listen to those who were promoting self-made religion. Paul is saying that God's appointed times are important because they are shadows of the Messiah and the world to come and teach important things about him, so don't let anyone talk you out of obeying God's commands. Consistently throughout the Bible, man's traditions are rejected while God's commands are upheld. Furthermore, Colossians 2:8 would be pitting Jesus against the Father, as though Jesus were in disagreement about which laws should be obeyed. Jesus said he came to do the Father's will, not to oppose it.
In Galatians 4:10 Paul writes that he fears that he labored over the Galatian Gentile congregations in vain because they were now observing “special days, months, seasons and years.”
Galatians 4:8-10 Formerly, when you did not know God, you were enslaved to those that by nature are not gods. 9 But now that you have come to know God, or rather to be known by God, how can you turn back again to the weak and worthless elementary principles of the world, whose slaves you want to be once more? 10 You observe days and months and seasons and years!
Paul said he was speaking to those who formerly did not know God, so he was speaking to former pagans. They were not formerly keeping God's commands, so they could not be turning back to them. Weak and worthless elementary principles of the world again could not be referring to God's holy, righteous, and good law, but to self-made religion. So whatever Paul is referring to in verse 10 is within the context of pagan practices, not about following God's appointed times. It seems bizarre that someone who thinks that Jews should still keep God's law would argue that Paul, speaking as Jew, was referring to it as weak and worthless elementary principles of the world.
But Paul never qualifies his argument this way. He never writes anything like “for a discipled life of blessing, you all need to keep the whole Torah
This is an argument from silence, but it should be obvious that followers of God should obey His commands.
we cannot simply transfer the practices of pre-Yeshua times into the New Covenant period.
Why not?
Torah itself makes it clear that the Law has different applications for different groups. For example, purity laws and requirements for priests were different than purity laws for other Israelites. There were laws for men and laws for women, laws for widows, children, and so on. The Torah is not one homogenous whole, but is filled with diversity. Only as each group fulfilled its own destiny in Torah (men and women, for example) could there be true unity in the nation. Likewise, unity of Jew and Gentile does not require that there be one set of commandments for both, but that each group fulfill its own identity and destiny (1 Cor. 7:17-20).
Both Jews and Gentiles are required to have a righteous and holy conduct (1 John 3:10, 1 Peter 1:13-16). It's that simple. All of God's chosen people should follow His laws for how to have such a conduct. Paul saying that Jews should remain Jews and Gentiles should remain Gentiles does not indicate two different sets of commands.
It does not mean that Gentiles should be taught to keep all the details of law given to Israelites.
Why not?
Yeshua teaches mostly on those parts of Torah considered to be universal in accordance with Jewish teaching of that period. The Gospels give little space to the primary concerns of the Pharisees concerning Torah’s purity laws. From how to pray, to loving enemies, from lust in the heart to hatred in the heart, Yeshua teaches Torah that applies to all. There is no evidence that the Apostles ever taught Gentiles to keep the whole Torah, but only the Torah that was perceived as universal, just as Yeshua himself had done.
This runs contrary to Matthew 5:17-20.
As has been noted, these are very similar to the Noahide laws. This does not mean that Gentiles are free to murder, steal, and dishonor their parents. The passage assumes a universal morality, as do Paul, Peter, and James (who were present that day), and John in their writings. As Romans 2 notes, Gentiles can perceive the law of God, even without the revelation of Moses, and are responsible for many standards that are also expressed in the Bible. For example, classic Roman moral law taught the ideals of monogamous marriage, honoring parents, honesty and much more. The essential and unique addition of New Covenant ethics is the sacrificial example of Yeshua.
I see no good reason to think that anything God commanded in the Torah doesn't have universal morality, nor do I see good justification for assuming an exemption for a subset of God's laws while not allowing exemption for other of God's laws.
Thus, One Law teachers transform an ambiguous statement into a strong and unambiguous exhortation.
Again, it seems pretty clear to me, so I see no good reason to label is as ambiguous.
They apparently overlook, however, the fact that these words spoken in the council were not included in the apostolic letter that was circulated among the congregations. If this were such a crucial exhortation to Gentiles, it is amazing indeed that the apostles, under the guidance of the Holy Spirit, did not think it important enough to put in their letter!
Another unjustified argument from silence.
Even were we to say that Gentiles are free to embrace Torah, the calendar of Israel, and more, there is no word that there is any covenant responsibility for Gentiles to do so. Acts 21 reinforces this impression. Here James tells Paul of the rumor that he teaches Jews who embrace Yeshua to forsake Torah. This of course is not true. So, Paul demonstrates this to be a false rumor by his Temple involvement. James reminds Paul that Gentiles were freed from responsibility for the full weight of Torah. Neither Paul nor James gives the slightest hint that they were encouraging full Torah observance among Gentiles. Paul could have said, “Not only do I not teach Jews to forsake Moses, but I even encourage Gentiles to embrace more and more of the Torah as they come to understand and appreciate it.” This is the emphasis of the One Law teachers, but there is not one word in the New Testament that explicitly encourages Gentiles to grow in keeping the whole Torah.
The basic law structure remained the same between covenants. God did not change what it meant to have a holy, righteous, and good conduct. This is another argument from silence that could easily be turned around by Paul taking the opportunity to support the opposite view.
Galatians 5 is a watershed passage. Here Paul in the strongest terms exhorts Gentiles not to receive circumcision. Some One Law teachers want to allow a legitimate option of circumcision, so they add the proviso that it should not be done for the wrong reasons. Yet, this is not in the text. The New Covenant offers the fullness of God’s blessing upon Gentiles without the necessity of circumcision. This was not the case in the Mosaic order.
Roughly 80% of men in the US are circumcised, so either argue that Christ is of no value to them or allow that the reasons for getting circumcised are important.
One additional aspect of One Law teaching is very confusing. The teaching advocates that Gentiles keep Biblical law, such as the festivals. One would expect that they would look into the Bible to see how to celebrate those festivals. Instead, they resort to post-Biblical Jewish practices. When One Law people practice a Passover Seder, for example, they often follow the order of traditional Jewish practice: four cups of wine, salt water, hand washings, Elijah’s chair and much more.
Instead of being truly “Biblical,” the One Law teachers appropriate various aspects of these Jewish traditions. Unfortunately, there is very little in their literature that shows their followers the distinction between what is Biblical and what is from Jewish tradition.
This is perhaps a valid concern, but it cuts both ways. There is nothing wrong with following traditions that are in sync with the Bible and not contrary to it, but if there is a way that is more closely in line with what the Bible instructs, then I'm all ears.