There is nothing about "ontological" anything in John 10:30, if you look at the context its clear.
33 The Jews answered him, saying, For a good work we stone thee not; but for blasphemy; and because that thou, being a man, makest thyself God.
34 Jesus answered them, Is it not written in your law, I said, Ye are gods?
35 If he called them gods, unto whom the word of God came, and the scripture cannot be broken;
36 Say ye of him, whom the Father hath sanctified, and sent into the world, Thou blasphemest; because I said, I am the Son of God?
Furthermore, if John 10:30 is about ontological unity, then we are also God. Because Jesus wants US to be "one" like Him and His Father are ONE. It clearly means one as in, united in purpose
Let's first deal with the definition of "ontology." The word is a "noun," the branch of metaphysics dealing with the nature of being."
At John 10:30 Jesus has just said that the sheep are equally safe in His hand and in His Father's hand. The power of the Son is equal to that of the Father. Jesus is asserting the essential unity of the Father and the Son in the word "one" (hen). It is a neuter number to indicate equality of essence, attributes, design, will and work. (Someone already went over this.)
Jesus distinguishes the "I" from the "Father" and uses the plural verb "are" denoting "we are." Thus these words separate the persons within the Godhead, but "one" asserts their unity of essence or nature as identical. So, technically speaking Jesus is saying, "I and My Father we are one."
The Jews understood Jesus correctly. "Again" refers to John 8:59 at which time the Jews also attempted to stone Him for blasphemy. It should also be noted that many understand this verse to meaning the Father and the Son are one in purpose. It's already a "given" they are one in purpose but being one in purpose is not a "blasphemy" offense.
How do I know? John 10:33, "The Jews answered Him, "For a good work we do not stone You, but for blasphemy; and because You being a man, make Yourself out God." Now, if this is teaching the idea of "one in purpose" why does Jesus bring up Psalm 82:6, the subject of "gods?" Vs 34, "Has it not been written in your Law, "I said you are Gods?" Vs35, "If he called them gods, to whom the word of God came (and the Scriptures cannot be broken, vs36, do you say of Him , whom the Father sanctified and sent into the world, You are blaspheming, because I said "I am the Son of God?" So, my question is what is the point Jesus is trying to make from John 10:34-38?
IN GOD THE SON,
bluto