Did the Roman church follow the Mosaic Law? How about the Corinthian church? How about any of the churches in the NT?
Indeed. In Romans 2:13-14, Paul said that it was only the doers of the Mosaic Law who will be justified and that Gentile believers were by natures doers of it, and in Romans 2:25, he said that the way to recognize that a Gentile has a circumcised heart is by observing their obedience to the Mosaic Law.
The answer is no because of Acts 15.
Jesus never taught us to follow the Mosaic law, He taught us to follow Him,...
Joh 14:12 Truly, truly, I say to you the one believing into Me, the works which I do, that one shall do also, and greater than these he will do, because I am going to My Father.
In Matthew 4:15-23, Jesus began his ministry with the Gospel message to repent for the Kingdom of God is at hand, which was a light to the Gentiles, and the Mosaic Law was how his audience knew what sin is (Romans 3:20), so repenting from our disobedience to it is a central part of the Gospel of the Kingdom. Jesus also set a sinless example for us to follow of how to walk in obedience to the Mosaic Law and as his followers we are told to follow his example (1 Peter 2:21-22) and that those who are in Christ are obligated to walk in the same way he walks (1 John 2:6).
I about missed this,...again you're incorrect,....
Act 15:5 But there rose up certain of the sect of the Pharisees who believed, saying, It is needful to circumcise them, and to charge them to keep the law of Moses.
Act 15:6 And the apostles and the elders were gathered together to consider of this matter.
The decision out of that gathering was that Gentiles were not required to obey the law of Moses.
In Acts 15:1, men from Judea were wanting to require Gentiles to become circumcised in order to become saved, however, that was never the reason for which God required circumcision, so the Jerusalem Council upheld the Mosaic Law by correctly ruling against requiring circumcision for an incorrect reason. In Genesis 12:48, a Gentile who wanted to eat of the Passover lamb was required to become circumcised, so the Jerusalem Council should not be interpreted as ruling against a Gentile correctly acting in accordance with what God has instructed as if they had the authority to countermand God.
In Acts 15:5, Pharisees from among the believers agree with the men from Judea that Gentiles should obey the Mosaic Law, but did not agree that it was in order to become saved. In Acts 15:6-7, Peter made the case that Gentiles had heard and believe the Gospel message, which again called for our repentance from our disobedience to the Mosaic Law, so Peter was affirming the position that Gentiles should obey it. Likewise, in Acts 15:8-9, Peter made the case that Gentiles had received the Spirit, and in Ezekiel 36:26-27, God will take away our hearts of stone, give us hearts of flesh, and send His Spirit to lead us to obey the Mosaic Law, so again Peter was affirming the position that Gentiles should obey the Mosaic Law, but in Acts 15:10-11, he ruled that salvation is by grace rather than by circumcision that was proposed in Acts 15:1.
In Romans 10:5-8, it references Deuteronomy 30 as the word of faith that we proclaim in regard to proclaiming that the Mosaic Law is not too difficult for us to obey and that obedience to it brings life and a blessing, so if Acts 15:10 had been referring to the Mosaic Law as being a burden that no one could bear instead of salvation by circumcision, then they would have been in direct disagreement with God's word and they would have been denying the word of faith that we proclaim.