Q. 1. Was Jesus really the cousin of John the Baptist? Based on Matthew 3:13-17 when Jesus was baptised by John the Baptist and Luke 7:18-23 when John the Baptist questioned if Jesus was the long awaited Messiah, it appears that Jesus and John did not know each other.
A. 1. To answer the first question, were Jesus and John the Baptist cousins? The Greek text of Luke 1:36 simply tells us “your relative Elizabeth in her old age has also conceived a son.” It does not say how Mary and Elizabeth were related, nor how Jesus and John the Baptist were related. The reference to Jesus and John the Baptist being cousins originated from the common tradition. It was believed that since their mothers were related, Jesus and John must have been cousins.
The first reference to Jesus meeting John the Baptist is found in Matthew 3:13-17 when Jesus was baptised by John. It appears that they did not know each other prior to that time. How could that be? The apocryphal “Infancy Gospel of James” answers that question. Written around the mid-second century, it mentions that John’s mother Elizabeth fled with him to the hill country to avoid Herod’s slaughter of the innocent boys born around the time of Jesus. Based on this, it now becomes obvious that Jesus and John were not playmates during their childhood as they lived far apart.
So when John the Baptist questions the authenticity of the Messiah in Luke 7:18-23, it is because he did not know Jesus at the same level that cousins would know each other.
Those are the facts concerning Jesus' relationship to John the Baptist.