One should not treat the preaching of the law in isolation. The entire Word of God needs to be preached. This Word comprises both the law and the gospel. No one can preach the gospel while ignoring the accusation of the law. Theologically, the accusation comes first. How can the acquittal be announced before the accusation has been brought forward?
As accusation, the law always precedes the preaching of the gospel and resonates in it. However, by limiting oneself to the accusation, one would fall short of the mandate to preach God’s Word. By stopping after the word of the law, one cuts the gospel in half by eliminating its saving and purifying perspective. It causes despair without indicating the way back to God.
. . . It does not befit us to prescribe for the Holy Spirit how to do his work. We have the mandate to preach the gospel (as acquittal from the accusation of the law; i.e., in terms of both of these words). For some the accusation through the law will hit home, and for others, the graceful love of God for a sinner. At any rate, both need to be proclaimed: guilt and redemption; punishment and forgiveness; judgment and grace.
- J. van Genderen, W. H. Velema, Concise Reformed Dogmatics trans. Gerrits Bilkes and Ed M. van der Maas (Phillipsburg, NJ: P&R, 2008), 433-34.