Christ, in the work of mediation, acts according to both natures, by each nature doing that which is proper to itself; yet, by reason of the unity of the person, that which is proper to one nature is sometimes in Scripture attributed to the person denominated by the other nature. WCF 8.7
The Communicatio Idiomatum (the communication of properties) A doctrine that is related to the Hypostatic Union is the communicatio idiomatum (Latin for 'communication of properties'). It is the teaching that the attributes of both the divine and human natures are ascribed to the one person of Jesus. This means that the man Jesus could lay claim to the glory He had with the Father before the world was made (John 17:5), claim that He descended from heaven, (John 3:13), and also claim omnipresence, (Matt. 28:20). All of these are divine qualities that are laid claim to by Jesus; therefore, the attributes of the divine properties were claimed by the person of Jesus."
How is Christ a fit mediator? Christ meets the qualification of the mediator through the incarnation. Prior to the incarnation hw could not be a qualified mediator. He needs to be the God-man.
Resources
Geerhardus Vos on Christology and Covenant by Daniel Ragusa
Of Christ the Mediator by Robert Shaw
The Unipersonality of Christ by Louis Berkhof
The Humanity of Christ by Alan Cairns
The Person and Offices of Christ by John Battles
The All-Sufficiency of Christ by S. M. Baugh
Parties to the Covenant & The Covenant of Redemption by Charles Hodge
Of Christ The Mediator by A. A. Hodge
The Communication of Properties: A Post-Reformation Divergence between Lutheran and Reformed Theologies By Gregg R. Allison
A Communication of Attributes by Ligonier Ministries
Communicatio idiomatum, the communication of properties by Matt Slick
He Lay in the Manger without Leaving Heaven by Gavin Ortlund
Doctrine of the Kenosis in Philippians 2:5-8 by Alva J. McClain
Classical View of the Two Natures of Christ by Sam Storms
The Communication of Attributes by Green Baggins
The Reformed Doctrine of the “Communicatio” by R. Scott Clark
The One Mediator by Martyn Lloyd-Jones
One God, One Mediator by R. C. Sproul
The Necessity of a Divine Mediator by Daniel Hyde
Solus Christus: Our Only Mediator by Michael Horton
Christ, Mediator of the New Covenant by Thomas Watson
The Mediator of the Covenant, in His Person, Natures and Offices by William Whitaker
The Solemn Consecration and Nature of the Mediator by John Flavel
The Priestly Office by Louis Berkhof
Of Christ the Mediator by Robert Shaw
The Everliving Intercessor by Joseph Philpot
The Works of Jesus Christ as an Advocate by John Bunyan
Jesus our Defense by Tim Keller
The Difference Between a Prophet and a Priest by Nick Batzig
Christ our Great High Priest by Martin Luther
Christ’s Priestly Action by Hugh Martin
Christ the Mediator by William Plummer
Jesus Christ the Covenant Mediator by Kim Riddlebarger
The Triple Cure Jesus Christ - Our Prophet, Priest and King by Kim Riddlebarger
Christ, Our Surety by RIchard Sibbes
Through the Westminster Confession Chapter 8.1 by William Vandoodwwaard
Jesus Christ, the Mediator by Geneva Institute
eBooks
On the Mediator (eBook) by John Calvin
The Fountain of Life: a display of Christ in his essential and mediatorial glory (eBook) by John Flavel
Christ Set Forth (eBook) by Thomas Goodwin
The Heart of Christ in Heaven (eBook) by Thomas Goodwin
The Glory of Christ (eBook) by John Owen
The Lord of Glory (eBook) by B. B. Warfield
Spiritual Union & Communion (eBook) by A. W. Pink
The Virgin Birth by J Gresham Machen
Christ: A Complete Saviour or the Intercession of Christ and Those Who Are Privileged in It (eBook) by John Bunyan
Christ the Mediator by Charles H. Spurgeon, Thomas Boston, Thomas Watson, London Baptist Confession, John Gill, William Whitaker
Multimedia
Of Christ the Mediator (Ch.8, Sec.6-7) by Greg Bahnsen
Books
A Dialogue on the Two Natures in Christ by Peter Martyr Vermigli