This is from Acts 15, which is mostly on the Council of Jerusalem:
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.”
The apostles and elders met to consider this question. After much discussion,
Peter got up and addressed them: “Brothers, you know that some time ago God
made a choice among you that the Gentiles might hear from my lips the message
of the gospel and believe. God, who knows the heart, showed that he accepted
them by giving the Holy Spirit to them, just as he did to us. He did not
discriminate between us and them, for he purified their hearts by faith.
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? No! We believe
it is through the grace of our Lord Jesus that we are saved, just as they are.
This law was declared obsolete by the council, not by Paul, and this was in the days of the Apostles, not in, “modern Christianity”.
The first part of that passage seems to be hyperbole, which Jesus often used. But He said the Law will disappear, “when everything is accomplished”, referring to His crucifixion and resurrection.
You seem to be caught on the word, “abolished”. The law wasn’t abolished, it became obsolete and unnecessary, as declared by the council in Acts 15. Jesus fulfilled the law because Moses taught that, “everything” would be explained by the Hebrew prophet (called, “the Prophet” by the Jews). The law had a purpose, as Paul explains, to help the Isrealites understand sin and that performing rote rituals would not set them free from that. They would be set free by being born again, which Jesus made possible by his sacrifice.