The epistle (2 Peter 3:3-13) describes the second coming of Christ, who, after resurrection from crucifixion, creates the second coming of a new world, the first having been lost in the great flood; and the coming of the new world will be in the fire of the day of judgment in which the unrepentant and the godless will be cast into eternal damnation in the hellfire of perdition—conflagration, it seems, a universal and omnipresent characteristic of the day of reckoning from the One who is “a thief in the night.”
The gospel is Matthew 25:31-46, which describes the emergence, mechanics, and elemental features of the Last Judgment. The last judgment is based on a simplicity of actions: if one helped the hungry, those with thirst, those who were strangers, and the naked and the sick and the imprisoned, and as the actions of such help apply beyond the individual act to all in need, the reward is life eternal; if one did none of these, the consequence is everlasting punishment.
I can suppose this is conceptually a good idea, but no generation has ever succeeded in applying it when it counts. Which is why we’ll not ever know where we will or will not end up—and this as we take with us everything that both the good and the bad cannot stop being intent to destroy.
Bach’s cantata, thus, advises the good to pray and watch, and the evil to be afraid; and, in it, the drama’s the thing. In the complex chorus that opens the work, Bach immediately places us in media res, the last trump sounding from the first bar; for the end of time is imminent. The subsequent bass recitative, elaborately and wonderfully accompanied by the orchestra, including the oboe and trumpet, first upbraids the sinners, and then soothes the sinless.