To distinguish is to learn. In the discussion of the doctrine of immediate regeneration it is of highest importance to take this seriously to heart. To neglect this entangles one in various difficulties and brings others into confusion, rather than clarifying their insight.
In connection with this doctrine, three questions need to be kept distinct.
First, in what manner does the Holy Spirit work within the human heart? Does He remain outside at a distance, and does He work in the human heart merely along those ordinary pathways to which we are bound in our interaction with other people, along the paths of understanding and volition, by word and example? Or does the Holy Spirit descend into the human heart such that nothing stands between Him and the inner being of the human person, and does He work within a person directly and irresistibly?
From this first question a second is to be distinguished. If the latter is the case, namely, if the Holy Spirit is present within a person immediately and performs His work directly, does not this direct operation exclude the use of means? If the operation of the Holy Spirit within the heart is immediate, does that not entail the claim that the use of means is superfluous, unprofitable, yes, even mistaken and detrimental?
Finally, a third question arises: If the immediate operation of the Holy Spirit in the human heart does not make the use of means superfluous or detrimental, how must we conceive of the connection that exists between the immediate operation of the Spirit and the function of the means?
The answer to the first question draws the boundary between those who confess sovereign grace and those who defend free will. The answer to the second question distinguishes those who maintain the power of the means of grace, from all so-called enthusiasts who consider the means of grace superfluous or denigrate them to empty signs. And the answer to the third question distinguishes between the Reformed on the one hand, and on the other hand the Roman Catholics, Lutherans, and others who restrict grace to, and confine it within, the means of Word or sacrament. The combination of the threefold answer assures the confessors of the Reformed religion a unique, distinct place among the churches of Christendom.
Saved by Grace (Grand Rapids, Michigan; Reformation Heritage; 2008) p. 9-10.