The Passover was kept at the full moon of the lunar month Nisan, the first of the Jewish ecclesiastical year; the Paschal lambs were slain on the afternoon of the, 4th Nisan, and the Passover was eaten after sunset the same day - which, however, as the Jewish day began at sunset, was by their reckoning the early hours of the r 5th Nisan; the first fruits (of the barley harvest) were solemnly offered on the 16th.
The Jews Celebrated Their Passover On The 14Th Day Of The First Month, That Is To Say, The Lunar Month Of Which The Fourteenth Day Either Falls On, Or Next Follows, The Day Of The Vernal Equinox.
In connecting the lunar month with the solar year, the framers of the ecclesiastical calendar adopted the period of Meton, or lunar cycle, which they supposed to be exact.
But every leap year one day must be added to the lunar month in which the 29th of February is included.
In Consequence Of The Solar And Lunar Equations, It Is Evident That The Epact Or Moon'S Age At The Beginning Of The Year, Must, In The Course Of Centuries, Have All Different Values From One To Thirty Inclusive, Corresponding To The Days In A Full Lunar Month.