Consequently, as time passed and the Lord tarried other interpretations of "behold I come quickly" began to be considered. Augustine gets a lot of the credit (blame) for this view, but his view requires that things that ought to be taken literally because they are written that way be seen as only symbolic. The rapture, tribulation, Armageddon, and so forth are all relegated to mere symbolism and are contained in a millennial age during which Christ is not physically present on earth, but rules through influence on Christian lives which, by the way, is exactly what he is doing today, and we are not in the Millennium.
So, if 1 Thessalonians is to be believed, (not to mention Jesus Himself, with proper understanding of the time reference) amillenialism can not be correct. Therefore, despite the fact that many churches support it, I hold it to be outside the bounds of orthodoxy (heterodox, if you like).