Here are the essential lines from Cameron:
Accordingly, ther are two kinds of decrees, one of them requires a condition, the other not. Those may be termed conditional, and the last absolut. Upon the first sort depends justification, and so that requires necessarily faith and repentance. On the last sort hangs effectuall calling, and that requires no conditions and dispositions. . . . The first decree, then, is to restore the divine image upon the creature, in a way wherein the rights of justice may be safe. The second is to send God’s Son into the world to save every one who believes in him, that is, are his members. The third is to render men fit and able to believe. The fourth is to save those who believe. The first two are generall, the last two speciall and particular. In our method of considering things, the principall are before the less principall. . . . But all this is to be understood as spoken of God, in a way accomodated to the infirmity of the human mind.
Essentially there are two kinds of decrees. The first two are conditional general decrees, and the second two are absolute particularist decrees. For Cameron, Amyraut, and Davenant, et al, conditional decrees were always subsumed under the revealed will of God. Conditional decrees never refer to ineffectual absolute or secret will decrees. For example, see Davenant on the meaning of conditional decrees here or here for more examples and explanations.
This now helps us to understand Amyraut:
21. And whereas they have made distinct Decrees in this Counsel of God, the first of which is to save all men through Jesus Christ, if they shall believe in him; the second to give Faith unto some particular Persons: they declared, that they did this upon none other account, than of accommodating it unto that Manner and Order, which the Spirit of Man observeth in his Reasonings for the Succour of his own Infirmity; they otherwise believing, that though they considered this Decree as diverse, yet it was formed in God in one and the self-same Moment, without any Succession of Thought, or Order of Priority and Posteriority.
The first decree there corresponds to Cameron’s conditional decree, and the second to his absolute decree.
So where does that lead us? It leads us to the fact that this “ordering” is in no way comparable to the standard infrar- or supralapsarian ordering. In both of those the standard orderings there is a string of absolute decrees; eg to create, permit the fall, election, to send the Son (for the elect), etc.
When folk like Warfield juxtapose the standard infra or supra ordering over and against Cameron’s or Amyraut’s, they are engaging in a simple category fallacy, comparing apples with oranges, or chalk with cheese as we say in Australia.
The two types of orderings should not be set side by side as if they are univocal orderings with the same univocal concept of decree.
And further, the Cameron-Amyraut order is purely set out as perceived from the human point of view, the ordo historia. We “see” creation, fall, and the public work of Christ (including “incarnation”), but we see” election and salvation as effectually enacted and applied to believers, after the fact. But such “after the fact” seeing is “secondary” to our starting point, which is creation, fall, and redemption, ie the public work of Christ.
This confirms my thought all along, that Amyraut’s detractors so framed his language to suggest that there were absolute decrees, what we today call the decretive will, being conditioned by the actions of men. In effect, ineffectual decretal volitions. But this is not what Cameron and Amyraut were saying at all.
Further, Warfield in his chart on the plan of salvation is just plain wrong in his wording of the second decree as being, “Gift of Christ to render salvation of all men possible.”1 That smacks of an absolute decree and does not mirror Cameron or Amyraut’s version at all.