God and Jesus are one
Jesus has the divine nature of God.
"For in Him dwells all the fullness of the Godhead bodily;" (Colossians 2:9, NKJV).
God and Jesus are father and son and they are one.
"Believe me that I am in the Father, and the Father in me: or else believe me for the very works' sake." (John 14:11, ASV).
"The works" are the healings, miracles, resurrections (people raised from the dead), the multiplying of food performed by Jesus. Demons can make people suffer greatly and Jesus cast out demons and delivered people from the oppression of the devil.
Jesus and God are one, and by the Holy Spirit (the glory) we can be one in them : "And the glory which thou hast given me I have given unto them; that they may be one, even as we are one;" (John 17:22, ASV).