A close proximity of the birth date of Jesus can be established examining both secular history and the Bible. Luke 3:1, 2 says that "in the fifteenth year of the reign of Ti·be´ri·us Caesar, when Pontius Pilate was governor of Ju·de´a, and Herod was district ruler of Gal´i·lee, but Philip his brother was district ruler of the country of It·u·rae´a and Trach·o·ni´tis, and Ly·sa´ni·as was district ruler of Ab·i·le´ne, in the days of chief priest An´nas and of Ca´ia·phas, God’s declaration came to John the son of Zech·a·ri´ah in the wilderness."
When was "the fifteenth year of the reign of Ti·be´ri·us Caesar" ? Secular history has established that Tiberius Caesar was named emperor on September 15, 14 C.E. by the Roman Senate, following the death of his stepfather Augustus Caesar on August 17, 14 C.E. Thus, fourteen years and some months later (or "in the fifteen year"), "God’s declaration came to John the son of Zech·a·ri´ah in the wilderness." The Romans did not use the accession-year system; consequently, the 15th year would run from the latter part of 28 C.E. to the latter part of 29 C.E.
John was six months older than Jesus (Luke 1:35, 36) and began his ministry (evidently in the spring of the year) ahead of Jesus as Jesus’ forerunner, preparing the way. Of Jesus, the Bible indicates he was born in the fall of the year, with the "shepherds living out of doors and keeping watches in the night over their flocks" (Luke 2:8), being about 30 years old when he came to John to be baptized.(Luke 3:21-23)
Therefore he was baptized, most likely, in the fall, about October of 29 C.E. Counting back 30 years would bring us to the fall of 2 B.C.E. as the time of the human birth of the Son of God.
At Daniel 9:24-27, it gives numerical information regarding the "Messiah", as to when he would "arrive" (not Jesus birth, but his becoming the Messiah). The angel Gabriel said to Daniel that "there are seventy weeks that have been determined upon your people and upon your holy city, in order to terminate the transgression, and to finish off sin, and to make atonement for error, and to bring in righteousness for times indefinite, and to imprint a seal upon vision and prophet, and to anoint the Holy of Holies. And you should know and have the insight that from the going forth of the word to restore and to rebuild Jerusalem until Messiah the Leader, there will be seven weeks, also sixty-two weeks......And after the sixty-two weeks Messiah will be cut off, with nothing for himself.....(of the seventieth week) and he must keep the (Abrahamic) covenant in force for the many for one week; at the half of the week he will cause sacrifice and gift offering to cease."
These "weeks" are not literal weeks, but years. Thus, the beginning of the "seventy weeks" of years (or 490 years) was in 455 B.C.E, or "in the twentieth year of Artaxerxes the king" of Medo-Persia (Neh 2:1) when Nehemiah was allowed to go to Jerusalem, "to restore and rebuild Jerusalem".(Dan 9:25; Neh 2:3-5)
Sixty-nine "weeks" of years (483 years from 455 B.C.E.) arrived in the year 29 C.E. (it need be remembered that there was no zero year between 1 B.C.E. and 1 C.E.) At this time, Jesus was baptized by John in the Jordan, most likely in the fall of the year.(Matt 3:13) Thirty years prior to this would bring Jesus birth to about the fall of 2 B.C.E.
Though Jesus birth had significance, it was not his birth that God looked upon with favor, but rather his death. The principle is stated at Ecclesiastes 7:1, which says: "A name is better than good oil, and the day of death than the day of one’s being born." Why would the "day of death" be better " than the day of one’s being born" ?
Simply put: At birth, no record of loyalty has been made, the slate is clean. On the other hand, at death, a person has shown whether or not he has a proven record of faithfulness toward God. It could be likened to buying a new car. It cannot be known as to how reliable that new car will be until perhaps a number of years has elapsed to show that it has been very dependable, and especially when there is a decision to replace it with another vehicle and having had a car that was trustworthy.
Hence, Jesus death has far more importance than his birth, for at his death, he was able to provide the critical ransom for dying mankind.(Matt 20:28) Had he proven disloyal before death, as Adam had, then the ransom would have been null and void in God's eyes.
With his perfect shed blood, Jesus was able to inaugurate the "new covenant" that replaced the "old Law covenant", for the apostle Paul wrote to the Hebrew Christians: "In his saying “a new [covenant]” he has made the former one obsolete. Now that which is made obsolete and growing old is near to vanishing away."(Heb 8:13)
The door to heavenly life, those selected by God as "kings and priests" of God's kingdom (Rev 5:9, 10), was now opened following his death, for Paul said: "Therefore, brothers, since we have boldness for the way of entry into the holy place by the blood of Jesus, which he inaugurated for us as a new and living way through the curtain, that is, his flesh."(Heb 10:19, 20)
Thence, on the night of Nisan 14, 33 C.E, hours before his death, Jesus "took a loaf, gave thanks, broke it, and gave it to them, saying: “This means my body which is to be given in your behalf. Keep doing this in remembrance of me.” Also, the cup in the same way after they had the evening meal, he saying: “This cup means the new covenant by virtue of my blood, which is to be poured out in your behalf."(Luke 22:19, 20; 1 Cor 11:23-26)