Christ did not teach abandoning the Law, circumcision, dietary restrictions, etc. That's where the disagreement between +Paul and the Apostles who knew Christ personally arose. To them, +Pauline gospel (he called it 'my gospel') rang foreign to what they remembered from Christ's teachings.
If this were true ... how could the Jerusalem Council (involving Peter, Paul, James, and others) ... agree to abandon circumcision as a requirement for Gentile christians ?
More importantly, if they were all inspired, and filled with Spirit, how could they be in disagreement?
It is the Spirit which works to bring our imperfect understandings ... into agreement ... with the Truth (of course).
He's obviously still working on it.
We are imperfect receivers ... if you will.
And again, looking at the issue from the opposite perspective, ...
Would we, could we ... agree on as much as we do ... without the guidance of the Spirit ?
It wasn't just circumcision; it was entire Judaism! You tell me how and why? Christ never said the Law did not apply because those who believe in Him are under grace. +Paul did. Justified under grace is not Judaism.
Even +Barnabas, who brought +Paul to Jerusalem, and was the only close friend of +Paul's at that time among Apostles, sided with +Peter and the rest.
The Church was dying. The Christians were being hunted (read up on the underground life of the Cappadocian Christians, where +Paul taught, living in carved out caved). Israel rejected Christ. In order for the Church to survive, it had to seek its existence elsewhere. Knowing the Gentiles would never accept Judaism, +Paul convinced the rest that it was "do or die."
It is the Spirit which works to bring our imperfect understandings ... into agreement ... with the Truth (of course)
Apostles had imperfect understanding, and they were inspired?
Would we, could we ... agree on as much as we do ... without the guidance of the Spirit?
I wouldn't give us that much credit. We don't even fully agree on the Holy Trinity or Christiology, although we may use the same words.
Two thousand years later, there is a huge body of Protestants who are agreeing only with themselves individually, a little bit here and a little bit there. There are 30,000 various Protestant 'churches' with their own theology and creeds. Even the Apostolic Church is in deep disagreement on some issues and has been for one thousand years.
The Church has failed miserably to stop secularization. In Europe 5% of the people attend church regularly. In America (some figures are over-inflated) the percentage is much higher, but America is a secular society through-and-through.
You call that a success? It's not the failure of the Spirit. We failed. Miserably.