Time-Reckoning in the Bible
The biblical day starts at sunset, hours are counted from sunrise, and the calendar runs on the moon. A working reference for how the Bible actually measures time, with modern clock and calendar equivalents throughout.
The Bible measures time on a completely different frame than a modern clock and calendar — the day begins at sunset, not midnight; daylight hours are counted from sunrise rather than a fixed “1:00”; the night is divided into military-style watches instead of hours; and the whole calendar runs on the moon, not the sun, with an extra month periodically inserted to keep the seasons and feasts aligned. None of this is trivia — knowing “the ninth hour” is mid-afternoon, or that “the third hour” is 9am, or that the day started the evening before, changes how several key narrative and prophetic details actually read. This note covers day/night divisions, the week, the lunar month, and the Jewish civil/religious calendar, with modern clock and calendar equivalents throughout. See Weights and Measures of the Bible for the companion note on length, weight, volume, and money.
Interpretive Notes Before Using This
- The day begins at evening. Gen 1:5 — “And the evening and the morning were the first day” — establishes the pattern followed throughout Scripture: a biblical day runs sunset-to-sunset, not midnight-to-midnight. This is why the Sabbath begins Friday at sundown and Passover is killed “between the evenings” on the 14th of Nisan but eaten that same Jewish calendar day, after dark.
- Two calendar starting points. Exod 12:2 — “This month shall be unto you the beginning of months: it shall be the first month of the year to you” — sets Nisan (Abib) as the start of the religious year, fixed at the Exodus. Israel’s older civil year began in the autumn month of Tishri instead (harvest/agricultural new year — the root of the modern Jewish New Year, Rosh Hashanah, still kept in Tishri). Both calendars run simultaneously throughout the Old Testament and rabbinic tradition.
- Lunar, not solar — with a patch. The Hebrew calendar’s months are lunar (~29.5 days each), which puts 12 lunar months about 11 days short of a solar year. Left uncorrected, the feasts (tied to agricultural seasons) would drift through all four seasons over time. The fix: a 13th month (Adar II / Adar Sheni) is periodically intercalated (inserted) in leap years to keep the lunar calendar roughly synced to the solar year — a system still used in the modern Jewish calendar.
- Roman civil time vs. Jewish time. By the New Testament period, Roman civil reckoning (day starting at midnight) coexisted with Jewish day-reckoning (sunset to sunset) — worth remembering when comparing Gospel timing details across different narrative conventions.
The Day
| Reckoning Point | Modern Equivalent | Note |
|---|---|---|
| Start of the day | Sunset (previous evening) | Gen 1:5; carried through the whole Bible |
| “First hour” | ~6-7 am | Daylight hours counted from sunrise, not a fixed clock |
| “Third hour” | ~9 am | Acts 2:15 — Pentecost, “it is but the third hour of the day” |
| “Sixth hour” | ~Noon | Acts 10:9 — Peter’s rooftop vision; Matt 27:45 — darkness begins |
| “Ninth hour” | ~3 pm | Matt 27:46 — Jesus’ cry from the cross; also a regular hour of prayer (Acts 3:1) |
| “Eleventh hour” | ~5 pm (roughly an hour before quitting time) | Matt 20:6 — the Parable of the Workers in the Vineyard |
| “Twelve hours in the day” | Full daylight span, sunrise to sunset | John 11:9 — Jesus’ statement to the disciples |
The Night — Watches
The night was divided into “watches” for the purpose of guarding a camp or city — a rotating shift system, not a clock reading. The number of watches changed between the Old Testament and New Testament periods.
Old Testament — Three Watches
| Watch | Approximate Modern Time |
|---|---|
| Beginning (first) watch | ~6 pm – 10 pm |
| Middle watch | ~10 pm – 2 am |
| Morning (last) watch | ~2 am – 6 am |
Judg 7:19 — “So Gideon, and the hundred men that were with him, came unto the outside of the camp in the beginning of the middle watch” — places Gideon’s raid around 10 pm.
New Testament — Four Watches (Roman system)
| Watch | Approximate Modern Time |
|---|---|
| Evening | ~6 pm – 9 pm |
| Midnight | ~9 pm – midnight |
| Cockcrowing | ~midnight – 3 am |
| Morning | ~3 am – 6 am |
Mark 13:35 — “Watch ye therefore: for ye know not when the master of the house cometh, at even, or at midnight, or at the cockcrowing, or in the morning” — names all four Roman watches directly. Peter’s denial is timed to the “cockcrowing” watch: Luke 22:34, 60 — “the cock shall not crow this day, before that thou shalt thrice deny that thou knowest me… and immediately, while he yet spake, the cock crew” — placing the scene in the dead of night, roughly midnight to 3 am.
The Week
A fixed 7-day cycle, unrelated to any lunar or solar phenomenon — unique among ancient calendars, and rooted directly in the creation week (Gen 2:2-3). The 7th day (Sabbath) is a day of rest built into the very structure of time itself, not tied to a harvest or moon phase the way most other ancient time-units were.
The Month
A lunar month (~29.5 days), historically fixed by observing the new moon. Because 29.5 isn’t a whole number, months alternated between 29 and 30 days in practice. New Moon observations were originally a live, watched event (announced by trumpet, cf. Ps 81:3), later fixed by calculation in the developed rabbinic calendar.
The Jewish Calendar — Months
| # (Religious) | Hebrew Month | Modern Equivalent | Notable |
|---|---|---|---|
| 1 | Nisan / Abib | March–April | Passover (14th), Unleavened Bread |
| 2 | Iyar | April–May | — |
| 3 | Sivan | May–June | Feast of Weeks / Pentecost (Shavuot) |
| 4 | Tammuz | June–July | — |
| 5 | Av | July–August | Fast commemorating both Temples’ destruction (9th of Av) |
| 6 | Elul | August–September | Month of preparation before the fall feasts |
| 7 | Tishri | September–October | Civil New Year (Rosh Hashanah), Day of Atonement (Yom Kippur), Feast of Tabernacles (Sukkot) |
| 8 | Cheshvan | October–November | — |
| 9 | Kislev | November–December | Hanukkah begins (25th, post-biblical/intertestamental) |
| 10 | Tevet | December–January | — |
| 11 | Shevat | January–February | — |
| 12 | Adar (Adar II in leap years) | February–March | Purim (14th-15th) |
The Year
- Religious year — begins Nisan (Exod 12:2), anchored to the Exodus
- Civil/agricultural year — begins Tishri, the older harvest-based new year
- Sabbatical Year (Shemitah) — every 7th year, the land rests: no sowing or reaping (Lev 25:1-7)
- Jubilee (Yovel) — every 50th year (the year after 7 full sabbatical cycles), debts released, land returned to original family ownership, slaves freed (Lev 25:8-17) — the ultimate Old Testament “reset” picture, later read typologically as a shadow of the total liberty found in Christ (Luke 4:18-19, Jesus reading Isaiah 61 and announcing “the acceptable year of the Lord” in the synagogue at Nazareth)
Notable Passages Where Time Reckoning Matters
- Matt 27:45-46 — The Crucifixion Darkness and Cry. Darkness falls “from the sixth hour… unto the ninth hour” (noon to 3 pm), and Jesus cries out “about the ninth hour” — knowing this is mid-afternoon, not evening, matters for the timeline: Jesus dies in the mid-to-late afternoon of the day before the Sabbath, explaining the urgency to remove the bodies before sundown (John 19:31).
- Luke 22:34, 60 — Peter’s Denial at Cockcrow. Placing the denial in the “cockcrowing” watch (roughly midnight to 3 am) situates it deep in the night, during the same hours Jesus is being interrogated before the Sanhedrin — the two scenes are happening in the same dark, exhausted hours.
- Matt 20:1-16 — Workers Hired at the Eleventh Hour. The eleventh-hour workers are hired with only about an hour of daylight left before the workday ends — the parable’s shock (equal pay for an hour’s work) only lands once the reader knows how little time was actually left.
- Acts 2:15 — “But the Third Hour of the Day.” Peter’s defense against the drunkenness accusation at Pentecost depends on the hour: 9 am was far too early in the day for the kind of public drunkenness being alleged.
- Exod 12:6 / Exod 12:2 — Passover’s Fixed Timing. The lamb is killed “between the evenings” on the 14th of the religious year’s first month (Nisan) — precise calendar and time-of-day placement that the Gospels deliberately align Jesus’ crucifixion with.
Word Studies
| Term | Language | Strong’s # | Meaning |
|---|---|---|---|
| Yom (יוֹם) | Hebrew | H3117 | Day; also used for longer indefinite periods (“in that day”) |
| Ashmurah (אַשְׁמֻרָה) | Hebrew | H821 | Watch (of the night); from shamar, “to guard, keep watch” |
| Chodesh (חֹדֶשׁ) | Hebrew | H2320 | Month; also “new moon” — the same word covers both the month and its opening sign |
| Shabbat (שַׁבָּת) | Hebrew | H7676 | Sabbath; rest, intermission |
| Shemitah (שְׁמִטָּה) | Hebrew | H8059 | Release, remission — the sabbatical year’s defining act |
| Yovel (יוֹבֵל) | Hebrew | H3104 | Jubilee; ram’s horn/trumpet — named for the trumpet blast announcing it (Lev 25:9) |
| Hōra (ὥρα) | Greek | G5610 | Hour — a daylight-counted division, not a fixed clock hour |
| Phylakē (φυλακή) | Greek | G5438 | Watch, guard-post — used for the four-watch New Testament night division |
Related
See Weights and Measures of the Bible for the companion reference on length, weight, volume, and money.