b. An emotional element (assensus). Barth calls attention to the fact that the time when man accepts Christ by faith is the existential moment of his life, in which he ceases to consider the object of faith in a detached and disinterested way, and begins to feel a lively interest in it. It is not necessary to adopt Barth's peculiar construction of the doctrine of faith, to admit the truth of what he says on this point. When one embraces Christ by faith, he has a deep conviction of the truth and reality of the object of faith, feels that it meets an important need in his life, and is conscious of an absorbing interest in it, — and this is assent. [Louis Berkhof, Systematic Theology, 504-5; in Louis Berkhof, Systematic Theology: New Combined Edition (Grand Rapids, MI: Eerdmans, 1996)]
On the nature of faith, the Reformed tradition do not have a consensus until recently (see Witsius and Turretin for example), and even then it seems no one knows exactly what to make of the 3 elements which are claimed to make up faith. Berkhof in later sentences admitted difficulties in drawing the various distinctions between the elements, albeit towards a reduction into the two elements of knowledge and trust, omitting "assent" altogether.
In his Systematic Theology, Berkhof defined assent as an emotional state, a state of feeling an interest in the subject of Christ. This is certainly interesting, if only that defining assent as emotions seem suspect. Does a person have to be in a certain emotional state ("assent") in order to trust ("fiducia") Christ?
What are some synonyms with "assent"? Doing a simple Google search will show results like "agree to," "accept," "approve," "consent to," and so on. In other words, "assent" is defined volitionally, not emotionally. I agree ("assent") with what I know ("notitia"), and thus I as an actor by an act of my will move from a state of "neutrality" or "disagreement" to a state of "agreement." It does not seem that any emotions are necessary for this act of the will.
As I had argued, the supposed third element "fiducia" has not always been the "third" element. I think part of the confusion over the elements of faith results in creative interpretation of even "assent" here. But if we define [saving] faith as being knowledge and an assent that leads to confidence (plerophoria), then I think we would have solved the confusion over the constitution of saving faith, without having "fiducia" become "faithfulness" as the Federal Visionists would want it, or, in Berkhof's case, making assent into an emotion.