Day-year principle

The day-year principle, year-day principle or year-for-a-day principle is a method of interpretation of Bible prophecy in which the word day in prophecy is considered to be symbolic of a year of actual time. It is used principally by the historicist school of prophetic interpretation. It is held by the Seventh-day Adventist Church, Jehovah's Witnesses, some Pentecostals and the Christadelphians. The day-year principle is also used by the Bahá'í Faith.

Proponents of the principle, such as the Seventh-day Adventists, claim that it has three primary precedents in Scripture:

Jon Paulien has defended the principle from a systematic theology perspective, not strictly just from the Bible.

This view was recognized by the Jews as seen in Daniel 9:24-27, and as seen in Jesus' use of the day-year principle in Luke 13 verses 31-33, and in the early church. The day-year principle was first used in Christian exposition in 380 AD by Tychonius, who interpreted the three and a half days of Revelation 11:9 as three and a half years, writing 'three days and a half; that is, three years and six months' ('dies tres et dimidium; id est annos tres et menses sex'). In the 5th century Faustus of Riez gave the same interpretation of Revelation 11:9, writing 'three and a half days which correspond to three years and six months' ('Tres et dimidius dies tribus annis et sex mensibus respondent), and in c. 550 Primasius also gave the same interpretation, writing 'it is possible to understand the three days and a half as three years and six months' ('Tres dies et dimidium possumus intelligere tres annos et sex menses'). The same interpretation of Revelation 11:9 was given by the later Christian expositors Bede (730 AD), as well as Anspert, Arethas, Haymo, and Berengaud (all of the ninth century).Primasius appears to have been the first to appeal directly to previous Biblical passages in order to substantiate the principle, referring to Numbers 14:34 in support of his interpretation of the three and a half days of Revelation 11:9. Haymo and Bruno Astensis "justify it by the parallel case of Ezekiel lying on his side 390 days, to signify 390 years ; — i. e. a day for a year. — ". Protestant Reformers were well established on the day/year principle and it was also accepted by many Christian groups, ministers, and theologians.

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