The comparison being made is between the peerless Scripture, and the Apocrypha. There is NO comparative authority between them. Just as I have NO authority in the church, relative to the authority of Jesus Christ. Whatever authority I have, as one of his ministers, compared to his personal authority--I have none.
The same is true for these books, sometimes treated as though they were on par with Holy Writ. All the more reason to strongly deny their authority, in comparison to the truly authoritative content of Scripture. The category distinction is too great to speak of even "lesser" authority in the same breath. They are of different orders.
Should we, then, like Kant, establish two 'realms' or senses, where merely human writings
cannot be said to be authoritative in the one, but
can be said to be authoritative in the other (i.e., "When considered in relation to Scripture merely human writings have no authority at all, but when considered in themselves or in relation to other merely human writings they do have [varying degrees of] authority")?
I haven't read much Kant, and therefore cannot even tell you anything abut the context of his statement. I'm not deliberately asserting anything "kantian." The dualism I am postulating is (in my view) neither kantian nor platonic, but Creator-creaturely. I do not believe in any "continuum" of either being or authority. As men, we do not share in the intrinsic authority of divinity. Ours is an analogous and derivative religious authority, it is "ministerial," it is real.
But it isn't inherent; it doesn't arise from within us. Nor can it be resident in an uninspired text. If an unispired text (like an unispired man) speaks with authority, it is speaking
with reference to the inspired text, or the divine Person. Thus, when the Confession speaks of the authority of Scripture, it puts it in a class-of-one. Any other authority is comparatively zero.
For another example, consider the word of our Lord, "ALL authority in heaven and in earth has been given unto me." How much
intrinsic authority does that leave for anyone else? It is not the case that there is a trove of authority, and the lower down we go, the less access we have to it; or the higher one rises, the more access he gets. Jesus, or God, isn't at the top of the food chain.
Once again, the issue isn't whether there are texts, persons, or institutions of earthly origin that may have real authority. Or even whether the church (as a heavenly organ) has real authority. The issue is of the
nature of the authority in question. And Scripture alone possesses authority of such a nature as makes it unique. And we are constrained in certain instances to speak of other authorities as having zero relative authority.
Jesus did not entirely deny the right or authority of those who "sit in Moses' seat." But that authority came to an abrupt end when it transgressed its bounds. Whereas, the authority of Scripture is boundlessly infinite, knowing neither spatial or temporal limitations. This is the sense in which the WCF speaks of the Apocrypha's (often till then bound within the covers of a Bible) purported power to bind conscience.