"But the natural man receiveth not the things of the Spirit of God: for they are foolishness unto him: neither can he know them, because they are spiritually discerned."
These last few verses of the 2nd chapter of the 1st epistle to the Corinthians furthers our understanding of the purpose of the Apostles initial, minimal restrictions on the Gentiles.
The Gentiles were pagans, born and raised, the Natural man. The Natural man cannot understand circumcision. As a man, I assure you that, in order for a grown man (over 18) to get circumcised he must have some knowledge and understanding about why and its purpose. Before someone can be asked to change their dietary habits, they must know(ledge) something about why its important. Even baptism seems like foolishness to the Natural man, because Baptism is an outward sign of an inward decision. Therefore it serves no natural purpose to the natural man.
In Chap.3 he goes on to say:
"And I, brethren, could not speak unto you as unto spiritual, but as unto carnal, even as unto babes in Christ. I have fed you with milk, and not with meat: for hitherto ye were not able to bear it, neither yet now are ye able. For ye are yet carnal: for whereas there is among you envying, and strife, and divisions, are ye not carnal, and walk as men?"
"For while one saith, I am of Paul; and another, I am of Apollos; are ye not carnal?
Who then is Paul, and who is Apollos, but ministers by whom ye believed, even as the Lord gave to every man? I have planted, Apollos watered; but God gave the increase.
So then neither is he that planteth any thing, neither he that watereth; but God that giveth the increase. Now he that planteth and he that watereth are one: and every man shall receive his own reward according to his own labour." (1Corinthians 3:1-8)
This type of behavior is still in practice today.
People believe what they believe despite what the Bible says, because of 'what my pastor said.'
Paul spoke to the gentiles like babes in the word because that's what they were. And he knew they did not have a Bible (new or old testament) that they could go home and read at their leisure.
"Now this I say, that every one of you saith, I am of Paul; and I of Apollos; and I of Cephas; and I of Christ.
Is Christ divided? was Paul crucified for you? or were ye baptized in the name of Paul?" (1Corinthians 1:10-16)
"To declare, I say, at this time his righteousness: that he might be just, and the justifier of him which believeth in Jesus. Where is boasting then? It is excluded. By what law? of works? Nay: but by the law of faith."
Because Jesus was righteous (did the Commandments), He can justify our mistakes, shortcomings, and pitfalls because of our faith in him. The law of faith; we do the Commandments because although we are not perfect like Jesus, He will justify our imperfections through our faith in Him.
For he is not a Jew, which is one outwardly; neither is that circumcision, which is outward in the flesh:
But he is a Jew, which is one inwardly; and circumcision is that of the heart, in the spirit, and not in the letter; whose praise is not of men, but of God.