280 days is the normal period of gestation. The ten curtains covering the Tabernacle were 28 cubits in length, a total of 280 cubits. The Bible associates gestation (the number 280) with a covering (see Psalm 139: 13). Biblical chronology shows that from Isaiah's prophecy—'Behold, a virgin shall conceive, and bear a son, and shall call His name Emmanuel' (Isaiah 7: 14)—given on 3rd May 742 BC—to 29th October 1 BC, when Jesus was born, was 280 x 888 days. (This measurement omits the days in which the Remnant of Judah were outside the land in captivity in Babylon, but this would need further elaboration than space permits here). Time periods relating to Jesus' life are measured in 'days' of 888 days and years.

This note is referred to in Chapter 17.