One method for estimating the start of the ministry of Jesus without reliance on the Synoptic gospels is to relate the information in the Gospel of John (2:13 and 2:20) about the visit of Jesus to Herod's Temple in Jerusalem with historical data outside the gospels about dates of the construction of the Temple.
John 2:13 states that Jesus went to the Temple in Jerusalem around the start of his ministry and in John 2:20 Jesus is told: "Forty and six years was this temple in building, and you want to raise it up in three days?".
Herod's Temple in Jerusalem was an extensive and long term construction on the Temple Mount, with worship and religious rituals performed during the multi-decade building process, which was never fully completed, not even by the time that the Temple was destroyed by the Romans in 70AD.
Having built entire cities such as Caesarea Maritima, Herod saw the construction of the Temple as a key, colossal monument.[56] The dedication of the initial temple (sometimes called the inner Temple) followed an 17 or 18 month construction period, just after the visit of Augustus to Syria.
Josephus (Ant 15.11.1) states that the temple's reconstruction was started by Herod in the 18th year of his reign.
But there is some uncertainty about how Josephus referred to and computed dates, which event marked the start of Herod's reign, and whether the initial date should refer to the inner Temple, or the subsequent construction. Hence various scholars arrive at slightly different dates for the exact date of the start of the Temple construction, varying by a few years in their final estimation of the date of the Temple visit.
Given that it took 46 years of construction, scholarly estimates for the Temple visit in the Gospel of John are around 27-29 AD.
The visit of Jesus to the Temple is part of the Cleansing of the Temple episode and, while some scholars consider it the same episode as that towards the end of Jesus' ministry in the Synoptic gospels (Mark 11:15–19 {Matthew 21:12–17 and Luke 19:45–48), other scholars believe that these refer to two separate incidents, given that the Gospel of John includes more than one Passover.
The dating of the episode at the beginning of the ministry of Jesus provides support to the view that there were two separate visits to the Temple.
Another approach to estimating an upper bound for the year of death of Jesus is the estimation of the date of Conversion of Paul the Apostle given that in the New Testament accounts Jesus' death takes place before this conversion. Paul's conversion is discussed in both the Letters of Paul and in the Acts of the Apostles, and in both accounts takes place after the death of Jesus.
In the First Epistle to the Corinthians (15:3-8), Paul refers to his conversion after the death of Jesus. The Acts of the Apostles includes three separate references to Paul's conversion experience, in Acts 9, Acts 22 and Acts 26.
The estimation of the year of Paul's conversion relies on a series of calculations that work backwards from the well-established date of his trial before Junius Gallio in Achaea Greece (Acts 18:12-17) around 51-52 AD, a date which gained historical credibility early in the 20th century following the discovery of four stone fragments as part of the Delphi Inscriptions, at Delphi across the Gulf from Corinth.
Most historians estimate that Gallio (son of the Seneca the Elder) became proconsul between the spring of 51 AD and the summer of 52 AD, and that his position ended no later than 53 AD. However, the trial of Paul is generally assumed to be in the earlier part of Gallio's tenure, based on the reference (Acts 18:2) to his meeting in Corinth with Priscilla and Aquila, who had been recently expelled from Rome based on Emperor Claudius' expulsion of some Jews from Rome, which is dated to 49-50 AD.
According to the New Testament, Paul spent eighteen months in Corinth, approximately seventeen years after his conversion. Galatians 2:1-10 states that Paul went back to Jerusalem fourteen years after his conversion, and various missions (at times with Barnabas) such as those in Acts 11:25-26 and 2 Corinthians 11:23-33 appear in the Book of Acts. The generally accepted scholarly estimate for the date of conversion of Paul is 33-36 AD, placing the death of Jesus before this date range.
The nativity accounts in the New Testament gospels of Matthew and Luke do not mention a day for the birth of Jesus. Karl Rahner states that given that the gospels were written as theological documents they do not pay attention to such details. Scholars such as E.P. Sanders consider the birth narratives non-historical and not a reliable method for determining the day of birth.
Neither Luke nor Matthew mention a season for when Jesus was born. However, scholarly arguments regarding the realism of shepherds grazing their flock at night during the winter have taken place, both challenging a winter birth for Jesus, as well as defending it by relying on the mildness of winters in ancient Israel and rabbinic rules regarding sheep near Bethlehem before February.
An indirect, and unsuccessful approach to determining the day of birth has been based on the statement in Luke 1:5-8 that John the Baptist, who was six months older than Jesus, was conceived around the time when his father, a priest in the division of Abijah, was on duty at the temple. The division of Abijah was the eighth among the 24 divisions to serve at the temple in strict order, one or possibly two weeks at a time. This has been used to argue for a birth date around The Feast of Tabernacles. If one assumes that the schedule of divisions at the temple always assigned the first division on the first week of the Jewish calendar, and proceeds with one division per week, with three one-week breaks around major festivals (thus allowing each division to serve twice a year), the first course of Abijah would occur in mid-Sivan (late May to early June), and it can be deduced that Jesus was born in mid-Tishri (late September to early October), or right around the Feast of Tabernacles. However, uncertainties regarding the exact schedule in place in 1st-century B.C. Israel are so substantial that the date derived this way is but one of multiple possibilities. One important reason to doubt this "solution" is that, when the Jerusalem temple was destroyed in 70 A.D. during the fifth month of the Jewish calendar, the division of Jehoiarib (first in the cycle) was on duty. It has recently been argued for a cycle that commenced each year on the first Saturday in Tishri (the seventh month), which would place the birth of Jesus in July or January.
The day of birth of Jesus, celebrated as Christmas is based on a feast rather than historical analysis. In the 1st and 2nd centuries, the Lord's Day (Sunday) was the earliest Christian celebration and included a number of theological themes. In the 2nd century, the Resurrection of Jesus became a separate feast as Easter and in the same century Epiphany began to be celebrated in the Churches of the East on 6 January. The festival of the Nativity which later turned into Christmas was a 4th century feast in the Western Church notably in Rome and North Africa, although it is uncertain exactly where and when it was first celebrated.
The earliest source stating 25 December as the date of birth of Jesus is likely by Hippolytus of Rome, written very early in the 3rd century, based on the assumption that the conception of Jesus took place at the Spring equinox which he placed on March 25th, and then added 9th months - festivals on that date were then celebrated. John Chrysostom also argued for a 25 December date in the late 4th century, basing his argument on the assumption that the offering of incense in Luke 1:8-11 was the offering of incense by a high priest on Yom Kippur (early October), and, as above, counting fifteen months forward. However, this was very likely a retrospective justification a choice already made rather than a genuine attempt to derive the correct birth date.
