Revised Julian calendar

Thus, Milanković's aim was to discontinue the divergence between the naming of dates in Eastern and Western churches and nations.

[4] In the end, for civil purposes, the Gregorian calendar was adopted; the changeover went into effect on 16 February 1923/1 March 1923.

The synod was chaired by Meletius IV and representatives were present from the churches of Cyprus, Greece, Romania and Serbia.

[10] The present vernal equinox year, however, is about 12 seconds longer, in terms of mean solar days.

On 15 October 1923, Patriarch Tikhon accepted the new calendar, but it caused disagreement among clergy, and 24 days later he reverted the decision.

[11] The present Russian Orthodox Church continues to use the Julian calendar for both its fixed festivals and for Easter.

The following is a scatter plot of actual astronomical northward equinox moments as numerically integrated by SOLEX 11[12][13] using DE421 mode[14] with extended (80-bit) floating point precision, high integration order (18th order), and forced solar mass loss[15] ("forced" means taken into account at all times).

SOLEX can automatically search for northern hemisphere spring equinox moments by finding when the solar declination crosses the celestial equator northward, and then it outputs that data as the Terrestrial Time day and fraction of day relative to 1 January 2000 at noon (J2000.0 epoch).

The progressive tidal slowing of the Earth rotation rate was accounted for by subtracting ΔT as calculated by the Espenak-Meeus polynomial set recommended at the NASA Eclipses web site[16] to obtain the J2000.0-relative Universal Time moments, which were then properly converted to Revised Julian dates and Jerusalem local apparent time, taking local apparent midnight as the beginning of each calendar day.

[17] The chart shows that the long-term equinox drift of the Revised Julian calendar is quite satisfactory, at least until AD 4400.

Evidently each of the authorities responsible for the Gregorian and Revised Julian calendars, respectively, accepted a modest amount of medium-term equinox wobble for the sake of traditionally perceived leap rule mental arithmetic simplicity.

This would conflict with the Church's historic practice of celebrating Christ's birth on 25 December, a date chosen for a number of reasons.

The emperor Constantine, writing to the bishops absent from the council to notify them of the decision, argued, "Think, then, how unseemly it is, that on the same day some should be fasting whilst others are seated at a banquet".

(This would not have been a problem if the recommendations of the 1923 synod to use an astronomical rule to reckon the date of Easter, as outlined above, had not been rejected.)

Furthermore, critics of the new calendar point out the advantage to celebrating Nativity separately from the secular observances of Christmas and New Year, which are associated with partying and alcohol consumption.

[citation needed] From a spiritual perspective, Old Calendarists also point to a number of miraculous occurrences that occur on the old calendar exclusively, such as the "descent of the cloud on the mount" on the feast of the Transfiguration.