Matthew 12:46, Luke 8:19, and Mark 3:31 say that Jesus’ mother and brothers came to see Him. The Bible tells us that Jesus had four brothers: James, Joseph, Simon, and Judas (Matthew 13:55). The Bible also tells us that Jesus had sisters, but they are not named or numbered (Matthew 13:56). In John 7:1-10, His brothers go on to the festival while Jesus stays behind. In Acts 1:14, His brothers and mother are described as praying with the disciples. Later, in Galatians 1:19, it mentions that James was Jesus’ brother. The most natural conclusion of these passages is to interpret that Jesus had actual blood siblings.
In each instance, the specific Greek word for “brother” is used. While the word can refer to other relatives, its normal and literal meaning is a physical brother. There was a Greek word for cousin, and it was not used. Further, if they were Jesus’ cousins, why would they so often be described as being with Mary, Jesus’ mother? There is nothing in the context of His mother and brothers coming to see Him that even hints that they were anyone other than His literal, blood-related half-brothers.
It does seem that one has to ignore the common sense use of the word
A second argument is that Jesus’ brothers and sisters were the children of Joseph from a previous marriage. The problem with this is that the Bible does not even hint that Joseph was married or had children before he married Mary.
There is no Biblical reason to believe that these siblings are anything other than the actual children of Joseph and Mary. Those who oppose the idea that Jesus had half-brothers and half-sisters do so, not from a reading of Scripture, but from a preconceived concept of the perpetual virginity of Mary, which is itself clearly unbiblical: “But he (Joseph) had no union with her (Mary) UNTIL she gave birth to a son. And he gave Him the name Jesus” (Matthew 1:25). Jesus had half-siblings, half-brothers and half-sisters, who were the children of Joseph and Mary. That is the clear and unambiguous teaching of God’s Word.
The above comes from
gotquestions.org/Jesus-siblings.html
I know the “until” arguments – they’ve been set forth on these boards several times. But it does seem that one has to do some fancy footwork around the plain meaning of the text in order to support the conclusions of Mary’s prepetual virginity and Jesus being an only child.
I was surprised to read that other Christian demoninations (some) believe Jesus had siblings.