Quartodecimanism

Quartodecimanism ("fourteenism", derived from Latin) refers to the practice of fixing the celebration of Passover for Christians on the fourteenth day of Nisan in the Old Testament's Hebrew Calendar (for example Lev 23:5, in Latin "quarta decima"). This was the original method of fixing the date of the Passover, which is to be a "perpetual ordinance". According to the Gospel of John (for example John 19:14 ), this was the Friday that Jesus was crucified in Jerusalem, the Synoptic Gospels place the Friday on 15 Nisan. A controversy arose concerning whether it should also be a resurrection holiday, and thus whether it should instead be celebrated on one particular Sunday each year, which is now the floating holiday that is commonly called Easter Sunday.

Background

Since the Bible's calendar is lunisolar and the Roman/Western calendar is only solar, it is difficult to calculate Nisan 14 in the western calendar without knowledge of how a lunisolar calendar system works. For various reasons, the Church eventually chose to use a different method from the one that the Jews had used for their Passover.

Quartodecimanism was popular among Christians in Asia Minor and it is generally believed that this was the method specifically preferred by the followers of John the Apostle , since it was advocated by Polycarp who was a disciple of either John the Apostle or John the Presbyter, assuming they are not the same person.

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