VERSE 1. With Barnabas, and took Titus with me also.
Paul chose two witnesses, Barnabas and Titus. Barnabas had been Paul's preaching companion to the Gentiles. Barnabas was an eye-witness of the fact that the Holy Ghost had come upon the Gentiles in response to the simple preaching of faith in Jesus Christ. Barnabas stuck to Paul on this point, that it was not necessary for the Gentiles to be bothered with the Law as long as they believed in Christ.
Titus was superintendent of the churches in Crete, having been placed in charge of the churches by Paul. Titus was a former Gentile.
VERSE 2. And I went up by revelation.
If God had not ordered Paul to Jerusalem, Paul would never have gone there.
VERSE 2. And communicated unto them that gospel.
After an absence of fourteen years, respectively eighteen years, Paul returned to Jerusalem to confer with the other apostles.
VERSE 2. Which I preach among the Gentiles.
Among the Jews Paul allowed Law and circumcision to stand for the time being. So did all the apostles. Nevertheless Paul held fast to the liberty of the Gospel. On one occasion he said to the Jews: "Through this man (Christ) is preached unto you forgiveness of sins; and by him all that believe are justified from all things, from which ye could not be justified by the law of Moses." (Acts 13:39.) Always remembering the weak, Paul did not insist that they break at once with the Law.
Paul admits that he conferred with the apostles concerning his Gospel. But he denies that the conference benefited or taught him anything. The fact is he resisted those who wanted to force the practice of the Law upon the Gentiles. They did not overcome him, he overcame them. "Your false apostles lie, when they say that I circumcised Timothy, shaved my head in Cenchrea, and went up to Jerusalem, at the request of the apostles. I went to Jerusalem at the request of God. What is more, I won the indorsement of the apostles. My opponents lost out."