John MacArthur on the rapture

Ok, we can talk about the merits of the "rapture" in more detail but my specific question is to the use of Rev 3:10 near the end of the video. (6:35) I feel like it is a stretch to take a passage that is directed to a certain gathering of believers in one specific place and apply it to the entire body of New Covenant believers. Taken in context of v.7 "And to the angel of the church in Philadelphia write:...." would it not be incorrect to then take v.10 "Because you have kept my word about patient endurance, I will keep you from the hour of trial that is coming on the whole world, to try those who dwell on the earth" and extrapolate that promise out over the whole of the New covenant Church?

After watching it, I think it is a stretch to say that the verse is for the church at large. It was specifically written to specific people. Not that we can't learn about God in it, but I am not sure I would base so much eschatology on it....