A. The covenant being made with Adam as a public person, not for himself only,
but for his posterity, all mankind descending from him by ordinary generation,¹ sinned in him, and fell with him in that first transgression.²

1Acts 17:26; 2Gen 2:16–17; Rom 5:12–20; 1 Cor 15:21–22.

Adam, as we saw in our exposition of WLC 20, was under a covenant of works or a covenant of life upon condition of personal, perfect and perpetual obedience of the Moral Law of God. But this covenant was not made with him as a private person. It was actually a covenant between God and all mankind. But as God had determined that all men (excluding the Lord Jesus Christ) would descend from Adam by natural generation (Acts 17:26), Adam was appointed as the representative or covenant head of all mankind in the covenant relationship. Although it was not in the eternal decree of God, it may be said from a speculative standpoint that had Adam kept the covenant all his descendants would have enjoyed life with him.

But Adam fell, and "all mankind descending from him by ordinary generation, sinned in him, and fell with him."

That is to say, all mankind, descending from him became covenant breakers, guilty of transgressing the covenant of works, and therefore worthy of death.

The fact that Adam was in such a position as the covenant head is clear from Scripture, especially as it compares Adam with the Lord Jesus Christ, who is the covenant representative of the elect in the Covenant of Grace. The apostle Paul makes this comparison in two passages.

The first passage is in Roman 5:12-21. Verses 18-19 reads:

Therefore as by the offence of one judgment came upon all men to condemnation; even so by the righteousness of one the free gift came upon all men unto justification of life. For as by one man’s disobedience many were made sinners, so by the obedience of one shall many be made righteous.

The second passage, 1 Corinthians 15:21ff, speaks of Christ as the second Adam, bringing resurrection while the first Adam brought death:

"²¹ For since by man came death, by man came also the resurrection of the dead. ²² For as in Adam all die, even so in Christ shall all be made alive.… ⁴⁵ And so it is written, The first man Adam was made a living soul; the last Adam was made a quickening spirit.… ⁴⁷ The first man is of the earth, earthy: the second man is the Lord from heaven." (1 Cor 15:21-22, 45, 47).

As our covenant head, Adam’s sin involved all mankind descending from him by ordinary generation. It is clear that all man descending from Adam by natural generation are on account of Adam’s guilt, born as guilty sinners (cf. Ps 51:5).

But how do we become sinners? What does our answer meant by saying that we "sinned in him"? What does the apostle Paul mean in saying "all have sinned" (Rom 5:12)?

The answer, we agree with Thornwell, is twofold. In the first place, all men are immediately imputed with Adam’s guilt because Adam is our covenant representative. "We are first charged with Adam’s guilt and then as a legal consequence, are born with natures totally corrupt" (James H. Thornwell, Works, 1.347).

In the second place, it does also appear that there is also a sense in which all mankind were seminally present in Adam and therefore actually "sinned in him" rather than being simply guilty in him.

Thornwell was referring to this aspect when he says: "I confess the leaning of my own mind to some theory which should carry back our existence to the period of Adam’s existence" (ibid., 349). This idea of seminal presence does not imply pre-existence of the soul. It has its basis in the Scriptural insistence that Levitical priests paid tithe to Melchizedek because Levi was in the loins of Abraham when he paid tithe to him (cf. Heb 7:5). But obviously, this does not imply that the grandchild of a robber is a robber because his grandfather robbed a bank. We speak of all mankind sinning in Adam because Adam was in the first place the chosen root and covenant head of the human race.

Thus, because of the special covenantal position that Adam held, all mankind descending from him by natural generation sinned in him and fell with him.

Why does our Confession emphasise the phrase "by natural generation"? This is emphasised because the Lord Jesus Christ was excluded from the guilt of Adam. Because of the principle of covenant representation and headship, which in the Scripture, is clearly accorded to the male head of family, the guilt of Adam is not imputed on the Lord, He being virgin-born. Likewise, the Lord Jesus was also not seminally present in the loins of Adam.

But Mary was a sinner as any other persons descending from Adam. How could the Lord be born through her without the natural corruption that infects every man? He was preserved from this corruption by the power of the Holy Spirit overshadowing her (see Lk 1:35).