Nativity of Christ - (Easton's Bible Dictionary)
The birth of our Lord took place at the time and place predicted by the prophets (Gen. 49:10; Isa. 7:14; Jer. 31:15; Micah 5:2; Hag. 2:6-9; Dan. 9:24, 25). Joseph and Mary were providentially led to go up to Bethlehem at this period, and there Christ was born (Matt. 2:1, 6; Luke 2:1, 7). The exact year or month or day of his birth cannot, however, now be exactly ascertained. We know, however, that it took place in the "fulness of the time" (Gal. 4:4), i.e., at the fittest time in the world's history. Chronologists are now generally agreed that the year 4 before the Christian era was the year of Christ's nativity, and consequently that he was about four years old in the year 1 A.D.