When God sends forth his holy gospel he deals with us in a twofold manner, first outwardly, then inwardly. Outwardly he deals with us through the oral word of the gospel and through material signs, that is, baptism and the sacrament of the altar. Inwardly he deals with us through the Holy Spirit, faith, and other gifts. But whatever their measure or order the outward factors should and must precede. The inward experience follows and is effected by the outward.
God has determined to give the inward to no one except through the outward.
For he wants to give no one the Spirit or faith outside of the outward Word and sign instituted by him, as he says in Luke 16:29, ‘Let them hear Moses and the prophets.’ Accordingly Paul can call baptism a ‘washing of regeneration’ wherein God ‘richly pours out the Holy Spirit’ (Titus 3:5). And the oral gospel ‘is the power of God for salvation to every one who has faith’ (Rom. 1:16).