In the context of the Bible, anniversaries are not explicitly mentioned as a regular practice or observance in the way modern society celebrates them. However, the concept of marking significant events and remembering them annually is present throughout the Scriptures. These commemorations often serve as reminders of God's faithfulness, covenant, and the history of His people.

Biblical Foundations

1. Passover: One of the most significant annual observances in the Bible is the Passover. Instituted in Exodus 12, the Passover commemorates the Israelites' deliverance from slavery in Egypt. God commanded the Israelites to observe this event annually: "This day is to be a memorial for you, and you are to celebrate it as a feast to the LORD. You are to celebrate it as a permanent statute for the generations to come" (Exodus 12:14). This annual celebration served as a reminder of God's mighty acts and His covenant with Israel.

2. Feast of Weeks (Pentecost): Another example is the Feast of Weeks, also known as Pentecost, which occurs fifty days after Passover. This feast is a celebration of the firstfruits of the wheat harvest and a time to remember God's provision. Leviticus 23:15-16 instructs the Israelites to count seven full weeks from the day after the Sabbath of Passover and then present an offering of new grain to the LORD.

3. Feast of Tabernacles: The Feast of Tabernacles, or Sukkot, is another annual observance commanded by God. It commemorates the Israelites' journey through the wilderness and God's provision during that time. Leviticus 23:41 states, "You are to celebrate it as a feast to the LORD for seven days each year. This is a permanent statute for the generations to come; you shall celebrate it in the seventh month."

Commemorative Stones and Memorials

Throughout the Old Testament, God instructed His people to set up stones or memorials to remember significant events. While not annual anniversaries, these served a similar purpose in reminding future generations of God's deeds. For example, after crossing the Jordan River, Joshua set up twelve stones as a memorial: "In the future, when your children ask, 'What do these stones mean to you?' you are to tell them, 'The waters of the Jordan were cut off before the ark of the covenant of the LORD. When it crossed the Jordan, the waters were cut off.' Therefore these stones will be a memorial to the Israelites forever" (Joshua 4:6-7).

New Testament Observances

In the New Testament, the concept of anniversaries is less formalized, but the early church did observe significant events. The Lord's Supper, instituted by Jesus during the Passover meal, is a regular observance that commemorates His death and resurrection. While not an annual event, it serves as a continual reminder of the new covenant: "For as often as you eat this bread and drink this cup, you proclaim the Lord's death until He comes" (1 Corinthians 11:26).

Modern Christian Practice

While the Bible does not prescribe specific anniversaries as they are celebrated today, the principle of remembering and commemorating God's work is deeply rooted in Scripture. Many Christians observe anniversaries of personal and communal significance, such as church anniversaries, wedding anniversaries, and other milestones, as opportunities to reflect on God's faithfulness and blessings.

In summary, while the Bible does not explicitly mention anniversaries in the modern sense, it provides numerous examples of annual observances and memorials that serve to remind God's people of His mighty works and enduring promises.Romans 14:5-6
One man esteems one day above another: another esteems every day alike. Let every man be fully persuaded in his own mind.
Topicalbible.org

For the Centenary Anniversaries of the Brethren's Eldership, and ...
... For the Centenary Anniversaries of the Brethren's Eldership, and the beginning of
the Society for the furtherance of the Gospel in the Moravian Church ...
/.../montgomery/sacred poems and hymns/hymn cclxxiii for the centenary.htm

Importance of the Anniversaries Connected with the Years 1894-1897 ...
... LECTURE I. Importance of the anniversaries connected with the years 1894-1897."
Christianity in Kent immediately before Augustine."Dates of Bishop Luidhard ...
/.../lecture i importance of the.htm

General Conference of 1824
... people by their Christian and ministerial deportment, as well as by their evangelical
labors in the pulpit, and on the platform at several of our anniversaries ...
/.../chapter 7 general conference of.htm

Early Plymouth
... Henry Ward Beecher, at that time pastor of the Second Presbyterian Church in
Indianapolis, who had come to New York for the May anniversaries, had made an ...
/.../griswold/sixty years with plymouth church/early plymouth.htm

St. Paul's Teaching on the Subject.
... and requests refreshment for him meanwhile, and fellowship (with him) in the first
resurrection; and she offers (her sacrifice) on the anniversaries of his ...
/.../tertullian/on monogamy/chapter x st pauls teaching on.htm

Elucidations.
... Offerings are made in honour of our departed friends, on the anniversaries of their
deaths, which we esteem their true birthdays, as they are born to a better ...
//christianbookshelf.org/tertullian/the chaplet or de corona/elucidations.htm

The Oration on Holy Baptism.
... our Salvation, and that far more than for weddings and birthdays, and namedays,
and house-warmings, and registrations of children, and anniversaries, and all ...
/.../cyril/lectures of s cyril of jerusalem/oration xl the oration on.htm

At the Feast of Tabernacles
... was once more begun. It was God's design that these anniversaries should
call Him to the minds of the people. But with few exceptions ...
//christianbookshelf.org/white/the desire of ages/chapter 49 at the feast.htm

On the Feast of the Apostles Peter and Paul (June 29).
... The whole world, dearly-beloved, does indeed take part in all holy anniversaries,
and loyalty to the one Faith demands that whatever is recorded as done for ...
/.../leo/writings of leo the great/sermon lxxxii on the feast.htm

Epistle Lxxvi. To Mellitus, Abbot.
... in sacrifice to demons, they should have also some solemnity of this kind in a changed
form, so that on the day of dedication, or on the anniversaries of the ...
/.../the epistles of saint gregory the great/epistle lxxvi to mellitus abbot.htm

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