There are few teachers as clear and helpful as Fred Sanders.
Here is a lecture he gave for laypeople at the 2013 G. Campbell Morgan Theology Conference, sponsored by Biola University’s Torrey Honors Institute:
One of his teaching tools, which combines historical and systematic theology in a chart, is the “Chalcedonian Box”:
Elsewhere he explains:
The metaphor of a box emphasizes the doctrinal boundaries that are recognized by Chalcedon.
On the top, it affirms Nicaea 325 (contra Arianism) by demanding that Christ is God, consubstantial with the Father.
On the bottom, it affirms Constantinople I (contra Apollinarianism) by demanding that Christ is human, consubstantial with us.
The soteriological axioms “God alone can save us” and “what is not assumed is not healed” mark these boundaries out.
As for how the divine and human elements come together, Chalcedon marks out the right and the left with its four mighty negatives: no confusion and no change on the one hand (contra Monophysitism Eutychianism ), but no division and no separation on the other hand (contra Nestorianism).
See also my post, “Thinking through Christology“