The day of the Lord is a key theme among the prophets. Zephaniah uses the expression, or a variant thereof, more often than any other Old Testament writer. The exact expression the day of the Lord appears only three times in the prophecy (here and in Zephaniah 1:14 (2x)), but the concept appears numerous times. For example, Zephaniah 1 has phrases like the day of the Lord’s sacrifice (Zephaniah 1:8), on that day (Zephaniah 1:9–10), and the day of the wrath of the Lord (Zephaniah 1:18), all of which are synonyms for the phrase the day of the Lord. Other temporal designations appear, such as at that time (4x; Zephaniah 1:12; Zephaniah 3:19–20 (3x)) and then (2x, Zephaniah 3:9, Zephaniah 3:11). Furthermore, the Hebrew word for day (יום) appears in the singular twenty times in the prophecy, and every appearance is related to the proclamation of the day of the Lord. In total, this amounts to twenty-nine references in Zephaniah’s fifty-three verses to the day of the Lord. So, every major section of the book and even every unit should be linked to Zephaniah's teaching on the day of the Lord.¹

But what is the exact nature of the day of the Lord? Although there is an abundance of discussion on the topic, there is no clear consensus. What would help in this regard is if the origin of the expression in the Old Testament were known, but this too is uncertain. The main proposals have been that its origins were in ritual ceremonies,² holy war traditions,³ theophany,^4,5 or covenant.^6,7

Others have suggested this is not an either/or situation, and thus opt for more complementary positions. As an example, Cross indicates that the worship/ritual ceremonies and holy war traditions were complementary, and thus he joins them together, concluding that the day of the Lord is the day of victory in holy warfare; it is also the Day of Yahweh's festival.⁸ It is in fact possible to join the other possible contexts as well. Thus, the day of the Lord concept calls to mind, all at once, ritual, divine warrior/holy war, theophanic, and covenant language.⁹

When it then comes to Zephaniah’s concept of the day of the Lord, these various concepts appear: language of a divine warrior/holy war (Zephaniah 1:7, Zephaniah 1:14, Zephaniah 1:16), of a theophany (Zephaniah 1:15), of ritual (Zephaniah 1:7, Zephaniah 1:9), and of the covenant (curses of Deuteronomy alluded to in Zeph 1, and the hope of blessing on the day (Zephaniah 3:9–20). This is what leads scholars to propose a basic concept of the day of the Lord that entails all of these aspects: the day of the Lord is the day of the Lord’s coming, when he intervenes in human affairs. As King notes, divine involvement in human affairs is probably the most salient feature of Zephaniah's proclamation of the day of the Lord.¹⁰ Similarly, VanGemeren observes, The day of the Lord signifies first and foremost Yahweh's intrusion into human affairs. His coming (theophany) is portrayed in the conceptual imagery of Warrior, Judge, and the great King.¹¹