Apocalyptic theology in a nutshell

The central theme is not “justice” in the older sense of the reward of the righteous and the punishment of the wicked; it is the coming triumph of God independent of anything human beings can do “either good or bad” (Rom. 9:11). Postexilic Isaiah delivers an astonishing rebuke to the traditional distinction between the righteous and the wicked with these words: “all our righteousnesses are as filthy rags” (Isa. 64:6 KJV).

Summing up this brief overview, “apocalyptic” theology can be defined on the simplest level as the thought-world that emerged among the Hebrew people after the exile, in which the human situation is seen as so tragic and insoluble that the only hope for deliverance is from outside this sphere altogether.—Fleming Rutledge, The Crucifixion, 140

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A translation note on Isa 64:6: It is very probable that the "filthy rags" are used mentrual rags.

Wrap your head around this: Your righteousness is like walking into the presence of God and waving used tampons™ in his face and expecting a reward.
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