We know these passages are dealing with Christ and with Adam. (1 Cor. 15:22) "For as in Adam all die, even so in Christ shall all be made alive."
And we know that God calls Adam and Christ, the first Adam and the Last Adam. (1 Cor. 15:45) "And so it is written, The first man Adam was made a living soul; the last Adam was made a quickening spirit."
Many times Christians make the honest mistake of calling Christ the Second Adam. But Scripture doesn't call Him the Second Adam. It calls Him the Last Adam. And for a reason.
Each Adam represented their race. They are the head of their race. Their actions are applied to their race. Because Adam sinned, all his race sinned with him. Because Christ was obedient, all His race is obedient and receives the gift of life and righteousness. (Rom. 5:17)
For all those in the 'first Adam', there is nothing they can do to obtain eternal life. They can't lead a good life and be moral and earn eternal life. They are sinners because Adam sinned. They can't remove it no matter how hard they try. The only hope is to turn, by faith, to Jesus Christ, the Last Adam, and be saved. This places them 'in Christ', the Last Adam.
Adam is called 'the first Adam' because he was the 'first Adam'. There had never been another. He was the first representative head of the human race. Jesus Christ is called 'the Last Adam' because there will never be another. Jesus Christ is the Last Representative Head of the human race'
But, what about Jesus as the Second Man. Why is He called the Second Man when numerically He was not the Second Man?
(1 Cor. 15:47)
Quantrill
It was always God's plan to populate the earth with man and have man implement God's will upon earth. And the mankind that God would create would be perfect and God fearing and obedient to His laws and will.
Which means, when God created Adam and Eve and told them to be fruitful and multiply, (Gen. 1:28), it was the children of a perfect Adam and Eve born unto them that God had in mind. Making the children perfect and Godly also.
Just as it was God's will to have man exercise the Kingdom of God on earth, so it was always His plan that the Son, that Second Person of the Godhead (Trinity), would be born into the family of man as a Man, and would rule over the earth and perform all of the Fathers will.
When the Fall occurred, another seed line was introduced into the human race that was not 'of God'. Which meant that the earth would be populated by both those of God and those not of God. And Cain, who was numerically the second man after Adam, was born. But Cain was not of God. He was of the devil. (1 John 3:12) "Not as Cain, who was of that wicked one"
And it's interesting that when Cain was born Eve said, "I have gotten a man from the LORD". As though she expected the child to be from God. But Cain was not from God. He was of that wicked one.
It is my opinion that Christ is called the Second Man, because God always intended for Him to be the Second Man numerically from Adam. For to accomplish what (1 Cor. 15:45-46) says in calling Christ a 'quickening spirit'. When Adam was created he had a spirit, but it was a human spirit. And it was always God's plan to impart His Spirit to man, which would be done through Christ the Last Adam and Second Man. And didn't Christ do just that even prior to the coming of the Holy Ghost at Pentecost? (John 20:22) "And when he had said this, he breathed on them, and saith unto them, Receive ye the Holy Ghost."
Now, the fall changed the timing of Christ's being born into the family of man, but didn't change God's count. Because God's count was always based upon those of him. Have you noticed how when Cain's line is given in (Gen. 4:16-24) that nothing is said of how long they lived? Because it was not important to God. But with Seth's line, the Godly line, (Gen. 4:25-26) God gives the exact number of years each lived.
Had the fall not occurred Christ was the Last Adam and Second Man who would give the Holy Ghost to Adam's perfect descendants. A quickening or life giving spirit. But because the Fall did occur, Christ is still the Last Adam and Second Man and the Holy Ghost is given to those placing faith in Christ. And all the believing are counted from that Second Man, Christ.
Quantrill