Why Christmas is celebrated on January 7 by millions of Christians worldwide

Christmas is a great festival for Christians to celebrate the birth of Jesus Christ, who is a central figure in Christianity. To most Christians throughout the world, including Catholics and many Protestants; Christmas is on December 25 of every year. However, a significant number of Christians observe Christmas on January 7, approximately two weeks later. This reflects no disagreement over the importance of the holiday or the belief in Jesus' birth but rather calendar traditions and historical developments.It points to the use of different kinds of calendars. Early Christians used the Julian calendar, which was issued by Julius Caesar in 46 BCE. This was then used generally in the Roman Empire and was, in fact, adopted by many early Christian feast days, including Christmas, which falls on December 25 in the Julian calendar.In 1582, Pope Gregory XIII introduced the Gregorian calendar, which addressed the inaccuracies in the Julian calendar in its calculation of the solar year. The Gregorian calendar is more accurate and is currently the most widely used civil calendar worldwide. Most Christian churches, including the Roman Catholics and various Protestant churches, adopted the Gregorian calendar and set Christmas to December 25, following this calendar.However, many eastern orthodox and some Oriental orthodox churches did not adopt the Gregorian calendar for liturgical use and continued to stick to the earlier Julian calendar to celebrate some Church events in its festivals because the traditional Julian calendar is 13 days behind in its dates when compared to the Gregorian calendar. Hence, when December 25th is marked in the Julian calendar, it is equivalent to January 7th in the Gregorian/ secular calendar. Approximately 250-300 million Christians around the world observe Christmas on January 7th. These include several Eastern Orthodox Churches like the Russian Orthodox Church, the Serbian Orthodox Church, the Georgian Orthodox Church, as well as several others.In some countries, January 7th is an official holiday for Orthodox Christmas, in countries such as Russia, Ethiopia, Serbia, and Belarus, among others. In some countries, Christians have the opportunity to hold religious services on January 7th despite it not being an official holiday.It is important to add, however, that not all Orthodox churches celebrate Christmas on January 7. Others, mainly from the Greek, Romanian, or Bulgarian churches, use the Revised Julian calendar, which is closer to the Gregorian calendar; therefore, Christmas is celebrated on December 25. For Orthodox Christians, the Christmas on January 7 is a time of adoration, people gathering together, and liturgical custom. Most of the believers among them start off with a Nativity fast, a period of abstinence and preparation, up to Christmas Eve on January 6, usually culminating in the night liturgy or a praise service. On January 7, families go to church services, share festive meals, and participate in age-old traditions that vary with culture and region.In places like Ethiopia Christmas, known as Genna, includes local customs such as special games and festivals. Even though the dates of celebration are different, what Christmas essentially means to all Christian denominations remains the same, to celebrate the birth of Jesus Christ.Because of the calendar differences between the Julian and Gregorian systems, millions of Christians celebrate Christmas on January 7. Certain churches, adhering to the older Julian calendar, still celebrate Christmas Day as December 25 Julian, which was January 7 Gregorian in the modern calendar used by most of the world today. This is done to keep up with ancient traditions and ties believers in with the historical rhythms of the early Church.While most Christians today observe Christmas on December 25, the celebration on January 7 remains an indelible and relevant observance to the various Orthodox communities worldwide, connoting continuity with a rich cultural heritage of shared faith in the nativity of Jesus Christ.