The words "trump," and "trumpet" appear ninety-six times in the Old Testament. There are two Hebrew words which are translated "trump" or "trumpet" : shofar (שופר), a ram's horn used to signal Israel, which appears sixty-seven times, and chatsotserah (שופר), a metal trumpet used as a musical instrument, referred to twenty-nine times.
In the Greek New Testament, the word for trumpet is salpigx (σάλπιγξ), and it is found only twelve times. With the exception of Paul's comparison of an uncertain sound from a trumpet of warning to speaking of tongues, all of the New Testament references to trumpets have to do with future prophecy.
The reason I often present the number of times a word is used, is that the frequency reveals the significance of a term to Israel and to the Church. In today's example, both Hebrew words have to do with the everyday lives of the Jewish people. But for the Church, trumpets play no role except as the signal for the Rapture in 1 Corinthians 15:52, 1 Thessalonians 4:16, and Revelation 4:1. All other New Testament references speak of a time when God's judgment will fall upon Israel and the unbelieving world.
There is much disagreement concerning the "last trump" which signals the Rapture, and that of the seventh angel of Revelation. I believe the "last trump" referred to in the Rapture passages, has to do with the last trumpet call to the Church; it signals the end of the Church Age. It is the only reference to a trumpet being the "trump of God."
The seven trumpet judgments of Revelation have to do with the Tribulation period which is also known as the Time of Jacob's Trouble (Jer. 30:7), and Daniel's Seventieth Week (Dan. 9:24-27). The first six take place in the first half of the seven year agreement Israel makes with the antichrist (Rev. 8:7, 8, 10, 12; 9:1; 9:13); the last signals the beginning of the second half, which is designated as the Great Tribulation (Matt. 24:21).
Another obvious difference between the two is that the Church longs for the sound that will signal our "trip home." The opposite is true for Israel; if they are familiar with the events which begin with the sounding of the seventh trumpet of Revelation (Rev. 11:15 - 19:21), they have to be terrified.
A good test of where you stand is whether you rejoice or cringe when someone mentions the final trumpet sounding. As for me, I can't wait!