The Gospels of Luke and John also support Christ’s birth in 5 BC.
Christ’s baptism marked the beginning of His earthly ministry. The third chapter of Luke tells us that Christ was baptized in the 15th year of Tiberius Caesar. Tiberius’ predecessor, Augustus, died on August 19, 14 AD. Tiberius ascended the throne shortly thereafter. By inclusive reckoning, the period from August 19 to December 31, 14 AD was considered his first regnal year. Therefore, his 15th regnal year was 28 AD, the calendar year when Jesus was baptized.
The second chapter of John describes the details, early in Christ’s ministry, when He cleansed the temple in Jerusalem. The temple had been under construction for 46 years up to that time. The manner in which the work was performed did not interrupt temple services. Josephus’ “Antiquities” cites 19 BC as the date Herod started construction on the temple. Forty-six years later, we arrive at 28 AD.
Luke 3:23 says, “And when He began His ministry, Jesus Himself was about thirty years of age.” If His 30th birthday was in 28 AD, His year of birth would have been 3 BC. That’s too late. Christ was born before Herod’s death. Herod died in the spring of 4 BC shortly after the March 13th eclipse of the moon. Therefore it is most likely that Jesus celebrated His 32nd birthday in 28 AD. That would make 5 BC His year of birth.
Notably, Biblical evidence reveals that Jesus was baptized before the Passover in 28 AD. That Passover occurred on April 28th according to astronomical data. Assuming His 32nd birthday was later that year, He was 31 years of age when He began His ministry, supporting Luke’s proclamation that He “was about thirty years of age.”