Day
Day as the Period of Daylight
In its most basic sense, "day" in Scripture refers to the hours of light between sunrise and sunset. Genesis 1:5 establishes this meaning at the very beginning: "God called the light Day, and the darkness he called Night." The daytime was divided into recognizable periods — morning, noon, and evening (Psalm 55:17). In the earlier Old Testament period, time was reckoned by these general divisions. After the exile, influenced by Babylonian and later Greek systems, the day was divided into twelve hours (John 11:9). Jesus referenced this system when He said, "Are there not twelve hours in the day?" (John 11:9). These hours were not fixed in length as ours are; they varied with the seasons, always dividing the time between sunrise and sunset into twelve equal parts.
Day as a 24-Hour Period
The word "day" also denotes a complete cycle of day and night, what we would call a calendar day. In the Hebrew reckoning, the day began at sunset rather than at midnight, as reflected in the creation account's refrain: "And there was evening and there was morning" (Genesis 1:5). This sunset-to-sunset pattern governed Israel's religious observance, so that the Sabbath and other holy days began the previous evening (Leviticus 23:32). This practice continues in Jewish tradition to this day. The week consisted of seven such days, with the seventh designated as a day of rest (Exodus 20:8-11).
Day as an Indefinite Period of Time
One of the most theologically important uses of "day" is its application to indefinite periods of time. The Hebrew word can mean "when" or "at the time that," as in Genesis 2:4: "In the day that the LORD God made the earth and the heavens," where "day" encompasses the entire creative work. This usage appears throughout Scripture in phrases like "day of trouble" (Psalm 20:1), "day of his wrath" (Job 20:28), and "day of salvation" (2 Corinthians 6:2). The psalmist declares that "a thousand years in your sight are but as yesterday when it is past" (Psalm 90:4), and Peter echoes this: "With the Lord one day is as a thousand years, and a thousand years as one day" (2 Peter 3:8).
The Day of the Lord
Among the most significant uses of "day" in Scripture is the prophetic concept of the "day of the LORD." This phrase refers to a future time when God will intervene decisively in human history, bringing both judgment on the wicked and deliverance for the faithful. Isaiah describes it as a day "cruel, with wrath and fierce anger" (Isaiah 13:9). Joel calls it "great and very awesome" (Joel 2:31). Amos warns those who casually long for it: "Why would you have the day of the LORD? It is darkness, and not light" (Amos 5:18). In the New Testament, this concept is continued as "the day of the Lord Jesus" (1 Corinthians 1:8; Philippians 1:6) and "the day of God" (2 Peter 3:12), pointing to Christ's return in glory.
Figurative Uses of Day
Scripture employs "day" in several figurative ways. It can denote one's lifetime: "the days of Adam were eight hundred years" (Genesis 5:4). Jesus used it metaphorically for the period of opportunity: "We must work the works of him who sent me while it is day; night is coming, when no one can work" (John 9:4). Paul described believers as "children of light, children of the day" who should live with spiritual alertness (1 Thessalonians 5:5, 8). The apocalyptic use of "day" in Daniel and Revelation introduces further complexity, where days may represent longer prophetic periods (Daniel 12:11; Revelation 2:10).
Day in the Creation Account
The meaning of "day" in Genesis 1 has been one of the most discussed questions in biblical interpretation. Three main views have been held throughout church history: that the days are literal 24-hour periods, that they represent longer ages or epochs, and that they constitute a literary framework for presenting God's creative work. Proponents of each view point to different aspects of the text. The repeated formula "evening and morning" suggests defined periods. Yet the word "day" is used in Genesis 2:4 to summarize the entire creation, and the seventh day lacks the closing formula, suggesting it may extend indefinitely. What all perspectives affirm is the central theological truth: God is the sovereign Creator of all that exists.
Biblical Context
The concept of 'day' appears from the very first chapter of Genesis through the final chapter of Revelation. It is central to the creation narrative, the establishment of the Sabbath, the calendar of Israel's festivals, the prophetic literature (especially in the 'day of the LORD' passages in Isaiah, Joel, Amos, and Zephaniah), and the New Testament's teaching on Christ's return and final judgment.
Theological Significance
The multiple meanings of 'day' in Scripture reveal important truths about God's relationship with time. God exists outside of time yet works within it for human redemption. The 'day of the LORD' teaches that history is moving toward a divinely appointed climax. The Sabbath day establishes a rhythm of work and rest that reflects God's own pattern in creation. Jesus' declaration that He must work 'while it is day' underscores the urgency of redemptive mission within the limited span of human opportunity.
Historical Background
Ancient Israel reckoned the day from sunset to sunset, in contrast to the Roman system that began at midnight and the Egyptian system that began at dawn. The division of the day into twelve hours was adopted after the Babylonian exile, borrowing from Mesopotamian time-keeping systems. The Hebrew calendar was lunisolar, with months based on the moon's cycle and periodic intercalary months to keep it aligned with the solar year. Time was often measured by the sun's position or by the length of shadows, and sundials were known in the ancient Near East from at least the second millennium BC.