How Did Paul Get His Knowledge
Bible students know from Paul’s own testimony that he was well educated. “I am indeed a Jew, born in Tarsus of Cilicia, but brought up in this city at the feet of Gamaliel” (Act 22:3 NKJV). Luke also has this comment concerning Gamaliel, “Then one in the council stood up, a Pharisee named Gamaliel, a teacher of the law held in respect by all the people” (Act 5:34 NKJV) and from the SDA Commentary we learn:
“Gamaliel was the grandson of the famous Hillel (see Vol. V, p. 97), and a renowned teacher and prominent Pharisee in his own right. The mantle of Hillel appears to have fallen upon his shoulders, and he exercised leadership in his party from about A.D. 25 to 50. There seems little basis for the claim that he was one of four presidents of the Great Sanhedrin at Jerusalem, since the supreme office was always held by the high priest in the times prior to A.D. 70 (see v. 27). But there is no doubt that he was an influential man and greatly honored by the Jews. He was the first to receive the title of Rabban. This indicates the esteem in which his countrymen held him. Jewish tradition reveals him as the ideal Pharisee, a worthy representative of Hillel’s school, which was more tolerant and less legalistic than the opposing school of Shammai” (6 BC 184).
So Paul was schooled by one of the best of Jewish teachers, and he demonstrated the superiority of his education at Athens when he faced the philosophers in that center of learning.
While Paul testified to his education by man, he also claimed God as his source, “But I make known to you, brethren, that the gospel which was preached by me is not according to man. For I neither received it from man, nor was I taught it, but it came through the revelation of Jesus Christ” (Gal 1:11-12 NKJV).
The question is how did Jesus reveal the gospel to Paul?
As we read Galatians we begin to see that Paul’s defense of his gospel basically comes from two places – the personal experience of his congregations and from Scripture. We also see this in his other letter (Romans) dealing with the same basic issue of how a person is saved.
The Holy Spirit seems to work differently with different people. While some get visions, others are led to Scripture and yet others, such as Luke, were helped in compiling testimony and obtaining information from other sources. For Paul it was an eye opener during which the Holy Spirit opened up Paul’s vast store of knowledge gained through his education at Jerusalem, making sense of the whole thing in the light of the cross. It was much like Jesus did to His disciples after His resurrection. The knowledge was there; it only needed to be put together correctly like a picture puzzle. In fact Jesus prophesied that, “the Holy Spirit, whom the Father will send in My name, He will teach you all things, and bring to your remembrance all things that I said to you” (John 14:26 NKJV). I believe that, for Paul, it was more of a Bible study in which the Spirit guided him from Scripture to Scripture as he first sought to confirm Jesus as the Messiah and then to understand the gospel in the context of all of God’s revelation.
Paul must have asked why the Messiah had to die and what relationship it had to both the covenant at Sinai and the everlasting covenant. So the Holy Spirit’s instruction had to include an understanding of the sanctuary services and what it all symbolized. All of this was already in the Scriptures and only needed to be interpreted through the Holy Spirit’s illumination.

Paul on his way to Damascus was confronted by the Lord Jesus Christ. Paul was going to destroyed the Church at Damascus. Jesus said, why persecutes thou Me. Paul realized at that point the that Jesus and the church were One and the same person. God does not need another God He needs a Body, Jesus is the Head of the Church which is His Body. Paul said, in 2 Corinthians 3: 5,"Not that we are sufficient (enough) of ourselves to think anything as of ourselves; but our sufficiency is of God" Paul's revelation came not by man but from the LORD Jesus. We too will come to the same revelation of Jesus by Jesus.
Like most of the people, even St. Paul could not understand God on the day he had an encounter with God. It him years for this. He was a Pharisee to the core. So he had to slowly unlearn certain wrong ideas in the beginning. For example, you can see him teaching 'predestination'. He also considered that God created each one of us with the same casual manner of a potter making pots from a mound of clay. He taught that women are a bit inferior than men, women are created for men and men are not created for women, God is a reward-giving master to us, etc. But finally St.Paul grows and proclaims the pure un-adulterated Good News substantiated on the cross by Jesus, "God does not consider our sins against us." (2 Cor 5:19). While reading St.Paul, these things have to be kept in mind.
You raise a very important, though little known/appreciated, point Dr George concerning the developmental nature of human experience. I believe that what you have outlined is an essential consideration (among others) that is necessary to help a person to "rightly divide the Word of Truth" (2 Tim 2:15).
Should this same awareness of the developmental nature of humans in their learning and unlearning of God that Dr George hilights perhaps also be applied to Ellen White's writings?
I need a verse where Paul said that the knowledge acquired from Gamaliel is not worth.
How did Paul know so much detail about the Lord's return?
How did Paul use his wisdom on the missionary journeys?