Mike Reeves talks about Adam and Christ in these great audios on sin and evil. Once we frame creation and salvation as the story of two men we see things much clearer.
For one thing we're able to honour Christ not only as Substitute but also as Representative. And we need both.
You see Christ drinks the cup so that - in one sense - we don't have to (Mark 10:38). But in another sense we do drink the cup He drinks and are baptised with the baptism with which He is baptised (Mark 10:39). He does die for us so that we do not face that same judging fire - this is His substitution. But we also die in Him experiencing it as a purifying fire - this is His representation.
We tend to be good at 'substitution' talk but not so good at 'representation' talk. Consider this fairly common way of conceiving salvation and judgement...
Here the key players are the saved and the damned. Christ is not in the picture. But of course once we've set things up like this, Christ becomes extremely necessary. But He's necessary in that the cross becomes the accounting tool required to balance the justice books. Without the cross the story doesn't work. So in that sense Christ is central. But in effect, He's a peripheral figure only required because other factors are calling the shots.
When things are viewed like this, Christ is very much thought of as 'substitute' but not really 'representative'. And, when the details are pressed, even His substitution will start to look very unlike the biblical portrait.
We need a better formulation. We'll think of 1 Peter 4 and then tie this back to Adam and Christ.
In 1 Peter 4:17 it says that judgement begins with the house of God. It doesn't say 'Judgement avoids the house of God.' It begins there. It begins with Christ, the true Temple of God. It continues with the church, the temple of God in another sense. But then it flows out to the world - God's house in yet another sense.
Here humanity is judged. And this is where Adam and Christ will be so helpful for us.
The LORD pronounces His curse on Adam. And all humanity is in him. "Sin came into the world through one man, and death through sin, and so death spread to all men because all sinned." (Rom 5:12) It is a universal judgement. No exceptions. The only path to salvation is the path through judgement.
But Adam is a type of the One to come (Rom 5:14). He was only ever setting the scene for Christ to take centre stage. And He does so, assuming the very humanity of Adam as substitute and representative.
Here centre stage is not occupied by the two bodies of people (the damned and the saved). What's driving everything is the two humanities (Adam and Christ). And the former is expressly a type of the Latter. And the Latter expressly assumes the fate of the former. So that in all things Christ will have the preeminence! (Col 1:18)