Passage
In that day it shall be said to Jerusalem, Fear not; Zion, let not thy hands be slack.
In that day it shall be said to Jerusalem, Fear not; Zion, let not thy hands be slack.
Zephaniah 3:14 Exult, O daughter of Zion; shout, O Israel; rejoice and be glad with all the heart, O daughter of Jerusalem:
Zephaniah 3:15 Jehovah hath taken away thy judgments, he hath cast out thine enemy; the King of Israel, Jehovah, is in the midst of thee; thou shalt not see evil any more.
Zephaniah 3:16 In that day it shall be said to Jerusalem, Fear not; Zion, let not thy hands be slack.
Zephaniah 3:17 Jehovah thy God is in thy midst, a mighty one that will save: he will rejoice over thee with joy; he will rest in his love; he will exult over thee with singing.
Zephaniah 3:18 I will gather them that sorrow for the solemn assemblies, who were of thee: the reproach of it was a burden [unto them].
The verse centers on "shall", "said", "jerusalem", "fear", "zion", "hands", and "slack". It is saying that the verse draws attention to "shall" and "said", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 15's "Jehovah hath taken away thy judgments he..." into verse 17's "Jehovah thy God is in thy midst...", so "shall" and "said" belong inside that flow. In Zephaniah context, the local focus is covenant, worship, and faithfulness.
A plain takeaway is to answer the verse's own emphasis on "shall" and "said" with trust shaped by these words, not by a vague optimism outside the passage.