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A Trintological Catalog

Quote Originally Posted by Steven Avery
This is actually an interesting question.
The exegesis that says that this is referencing the Gospel of Luke, which was written c. 41 AD to the high priest Theophilus, I find interesting.
“Luke, by birth an Antiochene and by profession a physician, was for long periods a companion of Paul and was closely associate with the other apostles as well.... It is actually suggested that Paul was in the habit of referring to Luke's gospel whenever he said, as if writing of some gospel of his own: ''According to my gospel' " (H.E. 3.4.6).
Romans 2:16
In the day when God shall judge the secrets of men by Jesus Christ according to my gospel.

Romans 16:25
Now to him that is of power to stablish you according to my gospel, and the preaching of Jesus Christ,
according to the revelation of the mystery, which was kept secret since the world began,

2 Timothy 2:8
Remember that Jesus Christ of the seed of David was raised from the dead according to my gospel:

1 Corinthians 15:1
Moreover, brethren, I declare unto you the gospel which I preached unto you,
which also ye have received, and wherein ye stand;

This is discussed by various writers today, Rick Strelan has a couple of references and quotes Jerome:

Luke the Priest (2004)
Rick Strelan

Jerome writes in chapter seven of his Lives of Illustrious Men:

Luke a physician of Antioch (medicus Antiochensis) as his writings indicate was not unskilled in the Greek language. An adherent of the apostle Paul, and companion of all his journeying, he wrote a Gospel, concerning which the same Paul says, ‘We send with him a brother whose praise in the gospel is among all the churches’ and to the Colossians ‘Luke the beloved physician salutes you,’ and to Timothy ‘Luke only is with me.’ He also wrote another excellent volume to which he prefixed the title Acts of the Apostles, a history which extends to the second year of Paul's sojourn at Rome, that is to the fourth year of Nero, from which we learn that the book was composed in that same city... Some suppose that whenever Paul in his epistle says ‘according to my gospel’ he means the book of Luke and that Luke not only was taught the gospel history by the apostle Paul who was not with the Lord in the flesh, but also by other apostles. This he too at the beginning of his work declares, saying ‘Even as they delivered unto us, which from the beginning were eyewitnesses and ministers of the word.' So he wrote the gospel as he had heard it, but composed the Acts of the Apostles as he himself had seen.

The only tweak I might offer to this history is that Luke the physician may well have been a different Luke.

Well, more significant is the chronology issue. Luke wrote the Gospel in 41 AD, before he had lots of interaction with Paul. Thus, Paul would be adopting the Gospel, due to his closeness with Luke, not saying it was de facto his creation.

Samuel Davidson actually says the situation is essentially the reverse. The phrase "my gospel" led to the theory that it refers to Luke, starting with a reference from Tertullian. This section runs a few pages in both directions.

An Introduction to the Study of the New Testament, Critical, Exegetical, and Theological, Volume 1
Samuel Davidson

All that Tertullian says is, 'It is the custom to ascribe Luke’s digest to Paul.’ The report arose from an incorrect explanation of Romans ii. 16 where Paul uses the phrase, ‘my gospel,’ i.e. my preaching. But the fathers, knowing that Luke had been Paul’s companion, and supposing that a written gospel was meant, concluded that the apostle had dictated Luke’s. This is virtually acknowledged by Eusebius.

However, Samuel Davidson is drawing from Michaelis.

Introduction to the New Testament, tr., and augmented with notes (and a Dissertation on the origin and composition of the three first gospels) by H. Marsh. 4 vols. [in 6 pt.]. (1793)

Johann David Michaelis

An Illustration of the Hypothesis proposed in the Dissertation on the origin and composition of our three first Canonical Gospels. With a preface and an appendix to the whole; being a rejoinder to the anonymous author of the Remarks on Michaelis and his Commentator. By H. Marsh (1803)

Thus, my personal conclusions are left open.

Richard H. Anderson, author of the paper Theophilus: A Proposal writes about "my gospel" a number of times in blog articles:
dokeo kago grapho soi kratistos - Theophilus

According to my gospel
February 25, 2006

Eusebius wrote: “It is actually suggested that Paul was in the habit of referring to Luke’s gospel whenever he said, as if writing of some gospel of his own: ‘According to my gospel.’” [Rom 2:16; 16:25; 2 Tim. 2:8].

Rom 2:16 on that day when, according to my gospel, God judges the secrets of men by Christ Jesus.

When Paul says in Romans 2:16 “on that day when, according to my gospel, God judges the secrets of men by Christ Jesus” he in fact is discussing the Lucan understanding of the function and role of the Son of man as the eschatological judge at the end of days. According to Paul, Jesus “judges the secrets of men” by “searching the hearts of men.” This same idea is expressed by Luke as the beginning of his gospel: “Simeon blessed them and said to Mary his mother, ‘Behold, this child is set for the fall and rising of many in Israel, and for a sign that is spoken against (and a sword will pierce through your own soul also), that thoughts out of many hearts may be revealed.’”
The citing of Luke as scripture is extremely significant in many ways:

Paul cited the Gospel of Luke as scripture
May 29, 2007

Paul on occasion speaks of his message as "my gospel" (Rom. 2:16; II Tim. 2:8). The mindset, that Paul could not possibly be alluding to any writing when he used the expressions “my gospel” and “our gospel”, is one that needs to be addressed.

Lee Dahn reminds me that Paul, said in 1 Timothy 5:18, for the scripture says, “You shall not muzzle an ox when it is treading out the grain," and, "The laborer deserves his wages” and that Luke 10:7 states: “And remain in the same house, eating and drinking what they provide, for the laborer deserves his wages; do not go from house to house.” You will note the Greek phrase for “the laborer deserves his wages” is the same but I have having trouble posting the Greek.

According to Michael Pahl, “Paul consistently uses "receive" (paralambanō) and "deliver" (paradidōmi) language in "transfer of information" contexts to refer to humanly mediated teaching or tradition (Rom 6:17; 1 Cor 11:2; Gal 1:9; Phil 4:9; 1 Thess 2:13; 4:1; 2 Thess 3:6). This usage parallels contemporary Pharisaic and later Rabbinic "receive" and "deliver" language in reference to humanly mediated teaching or tradition (see e.g. Gerhardsson, Memory and Manuscript, 288-291).”