The present form of the book has selected and collected a variety of oracles which reflect the traditional forms of prophetic speech.The original form of the invective-threat (3.1-8), oracles against foreign nations (2.4-15), and the promise (3.9-13) has been preserved form an early oral stage, even if in somewhat altered state.However, there are signs pointing to an editorial activity which goes beyond the mere collecting of individual oracles.As most recent commentators agree, ch.1 is comprised of many parts of original oracles which have now been formed into a larger literary unit around the subject of the 'day of Yahweh'.Rudolph designates it a 'Kerygmatic unit'.Moreover, by connecting the woe oracles of 2.4ff. integrally with the preceding oracles (note the ki of v. 4) the level of eschatological intensity in the oracles against the nations has been raised appreciably and they have been drawn within the orbit of the one great divine event. Finally, the promise of salvation in 3.8ff. has been placed within a traditional pattern which has the the oracles of promise following upon threat and concluding the book.In my judgment, it seems very likely that the oracle of promise belongs to an early level in the development, and should not be dismissed as a late and foreign accretion.The signs of two different layers within the passage would argue against seeing the whole passage (3.9-20) as post-exilic.