Where in the OT is Paul getting his “last trump” and “twinkling of an eye”?
Paul knew the trumpet of Isa 27:12-13 (also Ps 47:5; Joel 2:1; Zeph 1:16-18) sounds at the same time the nation is being born “at once” / in “one day” in Isa 66:8 (with Ps 102:13; Eze 39:22; Zech 3:9; 12:10; 14:7). That is the same moment the AC is being destroyed in “one day” (Is 9:14; 10:17; 47:9) by the breath of the Messiah’s mouth / voice (Isa 11:4; 30:27-33; 31:8-9; 42:11-14; 66:6-8; Joel 3:16; Zeph 1:7, 14-18; Zech 9:14).
As Paul’s manifest use of the Septuagint’s translation of Isa 11:4 in 2Thes 2:8 makes clear, the AC is destroyed at the instant of the Lord’s return to judge the wicked, raise the dead, and assert His rod iron rule over the nations the “last trump” (1Cor 15:52; Rev 10:7; 11:15). It all lines up with the moment (“twinkling of an eye”) of His return like the lightning flashing across the sky (Mt 24:27, 29-31; Rev 1:7).
Obviously, the NT writers believe their OT, literally! They put the pieces together by the help and leading of the Holy Spirit. They are not advancing ‘new truth’ but unraveling the mystery of what stood written in the OT prophetic scriptures (Acts 26:22-23; Ro 11:25-29; 16:25-26; 1Pet 1:11). That’s the glory and compelling proof of the gospel, that it was all foretold!