Why is the Vatican against "The Son of God" movie? I didn't watch that movie, I watched a Catholic Maronite priest saying that the Vatican issued a warning about the movie saying that it's not about the true message of Christianity.

The priest added that the movie is more about how the Jews and the Freemasons think of the Christ. Therefore it is delivering a false message about Christianity and the Bible and the theology. The priest advised against watching the movie.

Why would the Vatican be against the movie? What messages does the movie have that would concern the Vatican?
There are many inaccuracies and omissions (listed roughly from worst to less worse):


The piercing of the side of Christ didn't show blood and water
spewing out!
Mary Magdalen was constantly a tag-along with the disciples: when
they were in the tempest in the sea and even during the "laying on
of hands" after the Resurrection!
Mother Mary was not in the Upper Room!
Peter denied Christ 3× in the morning, in broad daylight, not before
the cock crow, which we didn't even hear!
Peter's faith was portrayed as though it, not Peter himself, was the
rock upon which the Church is built, as though our faith makes the
Church. This is Protestant ecclesiology. The Church still exists
even when we are unfaithful.
"The gates of hell will not prevail" etc. was omitted in Jesus'
saying Matt. 16:18.
"Lead us not into temptation but deliver us from evil" was omitted
from the Our Father.
The renting of the veil was not explicitly shown.


Jews, Catholics, and Protestants were all consulted in making this film, so your Maronite priest friend is right about it being more Freemasonic, syncretistic, or naturalistic than Christian.

See this for more info.