This is another good point to consider (even if it probably isn't Laynton's point). Why if Paul wrote first and Luke wrote on the authority of Paul, why doesn't Luke quote or cite his master in a way that declares to the Pauline world - 'I write this in the name of or under the authority of Paul.' Rappers do this when they appear or have other rappers appear on their records - i.e. 'here is so and so' 'I am so and so' 'this is so and so's record but I am on it' etc. It is curious the manner that Luke would have written a gospel for or on behalf of Paul but really used 'Mark' who had little or nothing to do with Paul and then doesn't say 'this Luke y'all with a shout out to my homeboy Paul, holla Antioch.' How is a repurposing a gospel written by Mark on behalf of Peter accurately reflect representin' Paul in such a way that Paul's audience and churches would immediately accept this repurposing. It's beyond baffling when you walk through it step by step.The Apostle Paul and the Gospels Nowhere in Paul's letters does he quote from any of the four gospels and neither does he refer to any earlier gospel that may have preceded them. This may be because the gospels were not yet written or at least not in any sort of wide circulation in the churches. But similarly, the gospels do not mention Paul's writings, ending as they do at the death and resurrection of Jesus.
While we all take the claim that Luke wrote the gospel for Paul at face value because everyone says it so many times, the idea that Luke could have written a gospel on behalf of Paul after he died by stealing someone else composition - or that of a rival church - and also Hebrews (according to many Church Fathers) is beyond weird and incomprehensible. Paul has to say 'my homie Luke' it's my gospel (or be made to say so) while he was my life. He simply has to in order to get anyone to believe this forgery.