A. This is an interesting question, which comes up quite often. For the answer I refer to the noted Catholic historian, Giuseppe Ricciotti, in his The Life of Christ, Bruce Publishing Co. 1947, pp. 155-156, 161-162.
“One absolutely certain factor in determining the date of Jesus’ birth is that he was born before the death of Herod the Great, that is before the end of March or the beginning of April in 70 a.u.c. (From the year of the founding of the city of Rome) or 4 B.C., for it is certain that Herod died at that time. But how long before the death of Herod was Jesus born? Various considerations help us to narrow the possibilities before 750 a.u.c.
One is Herod’s order to put to the death all the children of Bethlehem “from two years old and under” (Mt. 2:16), for this supposes that the infant Jesus was certainly within those limits. Hence, we may argue that Jesus was born much less than two years earlier, because it is altogether reasonable to assume that Herod would allow an extra generous margin in order to be certain of his victim. This two-year period, however, does not date back from the death of Herod but from the visit of the Magi who furnished him with the basis for his reckoning. On the other hand, when the Magi came, they found Herod still in Jerusalem (Mt. 2L1ff.) whereas we know that the old king, seriously ill and steadily growing worse, moved to the warmer climate of Jericho before he died. We may justifiably surmise that this transfer of residence took place when the first cold of the winter of 749 a.u.c. set in, or four months before Herod’s death.
“This gives us the following sequence: the birth of Jesus; the arrival of the Magi in Jerusalem; the decree to slaughter all babies two years old and under; Herod’s departure for Jericho; the death of Herod. To determine the time relation between the two extremes – the birth of Jesus and Herod’s death – we must reckon with the two years indicated in Herod’s decree, remembering that they represent much more time than was necessary for this purpose, and then we must consider the four months we have just indicated. There is, besides, the interval between the birth of Jesus and the visit of the Magi, and here we know only that it could not have been less than the forty days of the purification (Lk. 2:22 ff.), for Joseph would certainly not have presented the child in Jerusalem and exposed him to such serious peril if his death had already been decreed there. On the other hand, this interval may be considerably longer than forty days. In conclusion, reckoning backward from the date of Herod’s death, we may conclude that the margin of time allowed in the two years decreed by Herod balances the four months and the two intervals we have just mentioned with a little extra period of time left over. Hence Jesus was born a little less than two years before the death of Herod, that is, at the beginning of the year 748 0f Rome or 6 B.C.
As to the death of Jesus, Ricciotti states: “All four Gospels explicitly and unanimously set the death of Jesus on a Friday (Mt. 27:62; Mk 15:42; Lk 23:54; Jn 19:31) during the Pasch. From John we learn that this is the third Pasch in Jesus’ public life. Now the month of Nisan, in which the Pasch was celebrated, began with the new moon, like the other months in the Hebrew lunar calendar; and the Pasch, celebrated on the fourteenth day of Nisan, coincided with the full moon.