There is scripture supporting both so I just need some clarification.
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Both. While his return will be accompanied by trumpets it will happen when not expected. Nobody ever expects a thief to come. Thieves don't announce their coming the day before they come! It's simply a word picture of how surprised people will be. He isn't a thief!
Since the star of Bethlehem and the angels' singing occurred at night for Christ's first coming, it is possible that Christ's second coming will also begin at night.
First there would be the glorious light shining from the east unto the west (Matt 24:27), probably towards dawn, catching everyone completely by surprise. Then some of the holy angels (Matt 25:31) will come down to secure the local area selected for Christ's return. Finally, Christ himself will return after sunup, descending from clouds exactly in the same way as he ascended (Acts 1:11). He will be accompanied by holy angels. The whole event will be broadcast around the world for everyone to see, and recorded for future generations as proof for the skeptical.
If there were a trumpet associated with the second coming it would seemingly provide an alert and mitigate the surprise intention. Since there was no trumpet at the first coming, a trumpet at the second coming isn't according to type.
Matt 24:31, a possible trumpet verse, is concerned with gathering together the elect in heaven; there is no indication that the trumpet would be heard on earth, any more than the seven trumpets in Revelation would be heard on earth. The trumpet of 1 Thess 4:16, is concerned with announcing the rapture, not with Christ's second coming to judge the nations. It doesn't say that the trumpet, blown by an angel, will be heard by the living on earth.
My opinion is that the rapture with its trumpet, and the second coming are two separate events. Distinguishing between the two will become clearer as bible interpretation continues to progress in the future.
Acts 1:9-11 says that Christ will return not in the manner of how He came, but in the manner the disciples saw Him go (descending to Earth vs. ascending to Heaven, appearing in the clouds vs. clouds obscuring Him, etc). However, instead of only a couple witnesses, it will be in view of the people of Earth. (Rev 1:7) The lightening coming from the East that is visible in the west is not referring to dawn here, but to the surprise factor and the widespread visibility (Luke 17:24).
As for the trumpet, it accompanies the Second Coming as the trumpet symbolizes gathering and judgement.The trumpet would not give warning of the day Christ is coming - it is part of the event. Note that in Matt 24:30, "All the tribes of the Earth will mourn, and they will see the Son of Man coming on the clouds of the sky with power and great glory'; this cannot be referring to a secret rapture. It is also is also doubtful that the blast of the trumpet call is a noise that only the elect hear, though it is possible the language is being figurative. It is in the same vein as I Cor 15:52 and I Thess 4:16.
Matt 24:31 is also not speaking of the Heavens where God resides, but of Earth's atmosphere. I Thess 4:16 is even more restrictive, having the meeting in the lower air where living things breathe. Mark 13:27 describes it as a gathering from the utter extremities of the Earth to the farthest parts of Earth's atmosphere.