John the Baptist and Jesus the Christ were instrumental in launching the movement we know as Christianity. There has been, and continues to be, extensive controversy over the key dates in the lives of these two men. More as a matter of curiosity than substance, we would like to know when they were born, when did they start their ministry, and when did they die?
I spent a considerable amount of time researching this topic for my novel. While it is impossible, based on current knowledge, to exactly pinpoint these dates, we can place them within a rather narrow window of history.
It is generally agreed among most scholars that Jesus was born between 6 and 4 BC. According to the biblical record, John was born before Jesus. It would appear they were born a few months apart based on the timing of Mary’s pregnancy versus the gestation of Elizabeth’s baby. They were both born before the death of Herod the Great, the Roman client king of Judea, calculated by most scholars as being in March or April of 4 BC (also a controversial date).
Since it would appear both John and Jesus were born in the same year, this suggests both were born in 6 or 5 BC. Jesus is supposed to have started his ministry when he was between 29 and 31 years old. This gives more credibility to 5 BC.
Was Jesus born on December 25, 5 BC? Unlikely. The selection of this date was made long after the death of both men by early church fathers, allegedly to replace (or displace) a pagan holiday. Given the relationship of the two pregnancies, astronomical and environmental data (including the timing of the harvest), it would appear John was born in March and Jesus was born in late September or early October, 5 BC.
And that is as close as we can get until archeologists find something new to adjust our calculations.
In order for Jesus to be baptized by John (as recorded in the gospels), his ministry must have started before Jesus was baptized. Given the lag time it takes for information to travel in the first century AD, and the time it would take for John to establish his reputation, it is likely Jesus heard about John’s ministry several months after John actually started baptizing in the Jordan River. That puts a constraint on the start date of ~ 27 AD. He had to be active and well known before Herod Antipas had his steamy affair and then married Herodias (who divorced his half-brother to marry Herod). That romp apparently happened about 27 or 28 AD, which fits nicely with a start date for John’s ministry in 27 AD. Given the time it would take to establish himself as a prophet, we can guess -with some conviction - that John likely started his ministry between July and October of 27 AD. For the sake of historical sanity, I picked July of 27 AD.
John was apparently jailed for his opposition to the marriage of Herod and Herodias in February of 29 AD, and beheaded in August of 29 AD. We can also reach this conclusion because we know John was beheaded before Jesus died, and if Jesus died in April of 30 AD then John would have died the prior August.
If we have an approximation for John the Baptist, we also have to fit the ministry of Jesus within the same date constraints. If John was active from July of 27 AD through February of 29 AD, then Jesus must have been baptized before February 29 AD. According to the gospels, Jesus was about 30 when he established his ministry. That puts a constraint of between 26 and 28 AD. If we match John’s ministry with the baptism of Jesus, it would appear he was baptized in 28 AD. He would have been 31 at the time of his meeting with John.
Neither John nor Jesus had a long ministry. John’s demise came when he criticized Herod for marrying Herodias.
The priests, the Sadducees, and the Philistines regarded Jesus as an unwelcome outsider. Indeed, the Gospels are full of challenges directed at him. Jesus made them look incompetent. They were very annoyed when Jesus overturned the money changer tables because he was intruding on their money making scheme. While the Romans do not appear to have been overly concerned about Jesus, the priests did not have to work very hard to convince Pilate that Jesus was guilty of sedition. In addition, if we review the activity described in Luke (which is probably our best reference for elapsed time), and consider the impossibility of travel in the rainy season, Luke describes a ministry that would last 18 - 24 months.
If Jesus was crucified when he went to Jerusalem for Passover, there are two possible dates. Passover started on Monday, April 18, 29 AD and Friday, April 7, 30 AD. By tradition, Jesus was crucified immediately after Passover on Friday. That suggests April 7, 30 AD is the best fit because Passover would have ended Thursday night after sundown, allowing the Priests to pursue the trial without violating Jewish law (yes they could ignore the fact that Friday was preparation day). They also knew they had to act Thursday night because Jesus would likely leave Jerusalem after the close of Passover on Friday.
Both John and Jesus were born in 5 BC. It would appear the ministries of both John and Jesus lasted no more than 20 months. John ~ July 27 AD to February 29 AD. Jesus ~ August 28 AD. to April 30 AD. John was beheaded in August of 29 AD. Jesus was crucified in April of 30 AD.
That’s the best I can do unless we discover additional definitive and reliable information that gives us a better handle on these dates.