The 'trump of God' is God's own voice: Rev 1:10,11 KJV: "I was in the Spirit on the Lord's day, and heard behind me a great voice, as of a trumpet, Saying... Rev 4:1 "After this I looked, and behold, a door was opened in heaven: and the first voice I heard was as it were of a trumpet talking with me which said, Come up hither and I will shew thee things which must be hereafter ". The church age of grace began on Pentecost and ends at the last trump of God (I Thessalonians 4:13-17, I Corinthians 15:51-57, Rev 19:1-9). I Thess 5:2-3 KJV "For yourselves know perfectly that the day of the Lord so cometh as a thief in the night. For when they shall say, Peace and safety; then sudden destruction cometh upon them, and they shall not escape". "For then shall be great tribulation" (Matt 24:15-21, Dan 12:11, II Thess 2:2-4 KJV). +I Thess 5:4-9 KJV "But ye, brethren, are not in darkness, that that day should overtake you as a thief... For God hath not appointed us to wrath, but to obtain salvation by our Lord Jesus Christ" http://www.freewebs.com/lyraheavenlymusic/preachingofthecross.htm . Revelation 20:4-5 KJV "and judgement was given unto them: and I saw the souls of them (great tribulation saints) that were beheaded for the witness of Jesus, and for the word of God, and which had not worshipped the beast, neither his image, neither had received his mark upon their foreheads, or in their hands; and they lived and reigned with Christ a thousand years. But the rest of the dead lived not again until the thousand years were finished. This is the first resurrection" (Rev 20:4-5). The 'first resurrection' is for those that belong to Christ and occurs at various times: (I) "But now is Christ risen from the dead, and become the firstfruits of them that slept... But every man in his own order: Christ the firstfruits" (I Corinthians 15:20-23); "And the graves were opened; and many bodies of the saints which slept arose. And came out of the graves after his resurrection, and went into the holy city and appeared unto many" (Matt 27:52-53). *(II) "afterward they that are Christ's at his coming" (I Cor 15:23, I Thess 4:13-17, I Cor 15:51-57, Rev 19:1-9). (III) "Then cometh the end... when he shall have put down all rule and all authority and power. For he must reign... the last enemy that shall be destroyed is death" (I Cor 15:24-26, Rev 19:11-21, Rev 20:1-5). Rev 20:6 KJV "Blessed and holy is he that hath part in the first resurrection: on such the second death (The Great White Throne Judgement - Rev 20:11-15) hath no power, but they shall be priests of God and of Christ, and shall reign with him a thousand years".