In that day thou shalt not be ashamed for all thy doings wherein thou hast transgressed against me; for then I will take away out of the midst of thee them that exult in thy pride, and thou shalt no more be haughty because of my holy mountain.
Zephaniah 3:9 For then will I turn to the peoples a pure language, that they may all call upon the name of Jehovah, to serve him with one consent.
Zephaniah 3:10 From beyond the rivers of Cush my suppliants, the daughter of my dispersed, shall bring mine oblation.
Zephaniah 3:11 In that day thou shalt not be ashamed for all thy doings wherein thou hast transgressed against me; for then I will take away out of the midst of thee them that exult in thy pride, and thou shalt no more be haughty because of my holy mountain.
Zephaniah 3:12 And I will leave in the midst of thee an afflicted and poor people, and they shall trust in the name of Jehovah.
Zephaniah 3:13 The remnant of Israel shall not work unrighteousness, nor speak lies; neither shall a deceitful tongue be found in their mouth: but *they* shall feed and lie down, and none shall make them afraid.
The verse centers on "thou", "shalt", "ashamed", "doings", "wherein", "hast", and "transgressed". It is saying that the verse draws attention to "thou" and "shalt", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 10's "From beyond the rivers of Cush my..." into verse 12's "And I will leave in the midst...", so "thou" and "shalt" 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 "thou" and "shalt" with trust shaped by these words, not by a vague optimism outside the passage.