These two natures constitute one Christ

Institutes of the Christian Religion (1559) - John Calvin

Book 2 - God the Redeemer

Chapter 14 - How the Two Natures of the Mediator Make One Person

Sections 1-3 - Explanation of the human and divine natures in Christ

Section 1 - Duality and unity

The Word became flesh - John 1:14 - doesn't mean Word was changed into, or mingled with, flesh. Unity of person made this so, not the confusion of substances, Word and flesh. Like we have a body and a soul in one person, but they are not the same thing.

Section 2 - Divinity and humanity in their relation to each other

This doctrine not "humanly devised:" Scripture abounds!

John 8:58; Col 1:15, 17; John 17:5; 5:17 all refer (not solely) to Jesus' divinity.

Isa 42:1; Luke 2:52; John 8:50; Mark 13:32; John 14:10; 6:38; Luke 24:39 all refer (not solely) to His humanity.

Can't separate these natures, though. They are united in His person.

Sometimes the divine nature is spoken of with human terms:

Acts 20:28; 1 Cor 2:8; 1 John 1:1

"For the sake of the union of both natures He gave to the one what belonged to the other."

Section 3 - The unity of the person of the Mediator

Christ, true man, with divine qualities: 

John 1:29; 5:21-23; 9:5; 8:12; 10:9, 11; 15:1.

The office of the Mediator carried out:

1 Cor 15:24-28; Phil 2:7-10; Mark 16:19; Rom 8:34.

We can't speak exclusively of only the human or divine nature.