Question

If Presbyterians do not believe in the immaculate conception, then do they believe in the divinity of Jesus Christ or was he just one who led a holy life (i.e., a saint)?

Answer

As Presbyterians we believe the Bible, the Word of God, which is revealed in both the Old and New Testaments, is inerrant (without error) and infallible (it contains no mistakes) because it is inspired by God, who used men to write what he wanted to reveal about himself and the way of salvation. The main focus of this revelation is upon the one who came into the world to save sinners, namely Jesus Christ. All four gospels contain Jesus' own claim to be the Son of God, and therefore divine—e.g., Luke 22:70, "They all asked, 'Are you then the Son of God?' He replied, 'You are right in saying I am.'" Jesus himself claimed to be divine, fully God as well as fully man. Therefore, as Presbyterians, we believe his testimony and therefore in his divinity.

One more matter needs to be mentioned. You seem to equate or confuse the Immaculate Conception of Mary with the Virgin Birth. It can be confusing but you need to know that, as Presbyterians, we reject the doctrine of the Immaculate Conception. The Bible nowhere teaches that Mary was without sin, which, as a former Catholic, I know is Roman Catholic teaching, official doctrine of that church. Rather, if you read the Magnificat in Luke 2 you will see that she called God her Savior—thus admitting she needed to be saved from her sin.

The doctrine of the Virgin Birth is the biblical doctrine that Jesus was born of Mary but conceived by the Holy Spirit—i.e., that Jesus had no human father, but rather, as the Son of God, was fathered by God the Holy Spirit.