Most of the population of our country professes the Christian faith, but most of these people still wonder why Christmas is always celebrated on the same day, regardless of the year, and its Resurrection occurs on different dates? Strange, isn't it? In fact, the reason for this was the disagreement of the churches, and initially the date of Easter was also fixed.
Dating history
The first Christians were Jews, and they celebrated the Resurrection of Christ on the fourteenth day of the month of Nisan. According to the modern calendar, this period falls on March-April. Already in 325 AD, the Holy Church decided that there would be no celebration of Easter with the Jews, and fixed a different date for this holiday. From that moment, the question arose of how to calculate the date of Easter, because now it has become floating. They secured the first Sunday after the first spring full moon for the main religious event. The latter also changed and was calculated on the basis of the vernal equinox.
According to this conclusion, the time of the celebration depended on the solar and lunar calendars and could fall from March 22 to April 25 according to the old style.
Lunar calendar calculation
Before calculating Easter day in the new year yourself, you should remember the main rule on which the calculations of both the Gregorian and Alexandrian Paschal are based: "The Resurrection of the Lord is marked by the first Sunday day following the spring full moon." The full moon in spring is considered the first if it comes after the day of the vernal equinox.
How to calculate Easter correctly, according to this requirement? First of all, you need to calculate the position of the moon, or rather, the date of the full moon in a particular year. For this, the Meton cycle is used: the full moon is repeated every 19 years. In the first year of our era, the moon was in position 2, therefore, the calculation of the circle of the moon will look like this:
(X-2) / 19
With the result obtained, the age of the moon is calculated on the first day of March. First, the golden number of the cycle is determined by adding the number 3 to the result of the previous calculation. After that, the age itself is determined:
(11 * golden number) / 30,
where 11 is the constant difference between the bases, and 30 is the number of days of the lunar month.
It is important to consider that it is not the calculation result itself that needs to be obtained, but the whole remainder during division, which will be the age.
How to calculate Easter next? It is necessary to subtract the result from 30, and then add to the answer 14. If this is the date before the equinox, then you need to count Easter from the next full moon. If the date fell on Sunday, then the Resurrection of Christ will be celebrated on the next Sunday day.
Calculation according to the formula
In the 18th century, the German mathematician Friedrich Gauss proposed to the Church his formula for calculating for the celebration of the Bright Holiday.
This principle is based solely on mathematical calculations and defines Easter according to the Gregorian calendar. The formula for calculating the Orthodox Easter looks similar, only the result obtained at the very end must be added to the difference between the old and the new calendar, which is 2 weeks. So, the actions must be performed in the following sequence:
- The numerical value of the desired year should be divided by 19, and calculate the whole remainder. He will be the first.
- Further, the same year is repeatedly divided by 4, and the remainder, called the second, is also calculated.
- The number of the year is once again divided by 7 and the whole remainder is also remembered.
- The first result obtained is multiplied by 19, 15 is added to it, after everything is divided by 30, and the remainder (fourth) is calculated.
- The second result is doubled, the third is multiplied by 4, and the fourth is multiplied by 6, after which all the results are added up and 6 are added to them.
- The final number is divided by 7, and the resulting balance determines the date of Easter.
If the end result is less than 9, then the holiday is dated March. The exact date is calculated by adding the number 22 and the balances numbered 4 and 5.
If the result is greater than 9, then the Resurrection will be celebrated in April and the exact date is determined by adding the same balances, only with the further calculation of the number 9 from them.
Now, in order to calculate the Orthodox Easter, it remains only to add 13 to the dates received, since it is on this number of days that the Gregorian and Julian calendars differ .
Calculation Example
In fact, determining the exact date of the main Christian holiday is not as difficult as it seems at first glance. To make it clearer how to calculate Easter, not taking into account the position of celestial bodies, below are the calculations of the date of the Resurrection of Christ in 2018 according to the mathematical formula.
So:
- The first action is the division of the year 2018/19 = 106, 21 ..., which means that the whole remainder will be 4.
- Now 2018/4 = 504.5. The whole remainder 2.
- Next 2018/7 = 288.28 ... The remainder will be 2.
- Now you should determine the fourth remainder - ((4 * 19) + 15) / 30 = 3.03, while the remainder is 1.
- Next 2 * 2 = 4, 2 * 4 = 8, 1 * 6 = 6. Now 4 + 8 + 6 + 6 = 24.
- Result 24/7 = 3.43, the remainder is 3.
- 3 + 1 = 18 - the sum of the balances is less than 9, which means the date is in March.
Thus, we get that the Resurrection of Christ this year will be celebrated on March 26 according to the old style and April 8 according to the new one, since 4 + 22 = 26.
More calculation options
It is easiest to determine Easter, knowing the exact date of the Pancake week, because it is on the fortieth day from its last day that the Holy Resurrection of the Lord is celebrated.
You can also use for this Alexandria Easter. How to calculate Easter in this way? It is necessary to calculate the value of the full moon, and if it is less than 32, then the full moon will be in March for the first time in spring, and if it is more, in April. In the latter case, the exact date is determined by calculating from result 31. The formula for this is as follows:
equinox + ((19 * (Y / 19) + 15) / 30)
Conclusion
It is not difficult to independently calculate the dates of church holidays, given all the rules. A lot of nuances, understood only by experienced people, can confuse an inexperienced person. Difficulties may arise in the calculations, because if at least one value is incorrectly determined, then the final result will be incorrect.
If such calculations seemed too complicated, then you can simply use the ready-made results of calculations for subsequent years:
- 2019 - 28.04;
- 2020 - 19.04;
- 2021 - 2.05;
- 2022 - April 24;
- 2023 - 04.16.
If you wish, you can try to calculate further dates yourself or find on various resources on the Internet.