John 17:10 - Wesley's Explanatory Notes

All things that are mine are thine, and that are thine are mine — These are very high and strong expressions, too grand for any mere creature to use; as implying that all things whatsoever, inclusive of the Divine nature, perfections, and operations, are the common property of the Father and the Son. And this is the original ground of that peculiar property, which both the Father and the Son have in the persons who were given to Christ as Mediator; according to what is said in the close of the verse, of his being glorified by them; namely, believing in him, and so acknowledging his glory.