Ebionism says that Jesus is PHYSICALLY the son of Joseph.
Ebionism often quotes this verse (LUKE 3:23)
Now Jesus began His ministry when He was 30 years old. He was, just as people had thought, the son of Joseph, who was the son of Heli.
Ebionism denies the virgin birth of Jesus Christ, that Jesus was the son of Joseph and Mary, put forth by the second century Jewish deviant sect known as the Ebionites (Hebrew - "the poor"). Source: The Early Church by Henry Chadwick, Eerdmanns 1967 and A History of the Christian Church by Williston Walker, Charles Scribner's Sons 1970
Ebionism is a denial of the deity of Christ.