Pierre Marcel in his excellent book Infant Baptism, takes several pages to discuss the similarities and differences between the Word and the sacraments. He clearly explains how the Word and the sacraments are the same and how they are different. Here are some good paragraphs explaining the priority of the Word over the sacraments. All italics are Marcel’s.
The Word is indispensable to salvation, but the sacraments are not. The sacraments, in fact, are subordinated to the Word; they are signs of the content of the Word and are joined to it. The Word, therefore, is definitely something apart from the sacraments, but the sacraments apart from the Word are nothing: apart from it they have neither value nor power. The sacraments are nothing less than, but nothing more than, a visible Word. All the benefits of redemption come to us from the Word and only through faith, but there is not a single benefit which can be received through the sacraments alone, apart from the Word and without faith.
It is for this reason that the preaching of the Word should precede the administration of the sacraments in order to teach us and bring to our knowledge the significance of the visible sign. The words which are call “sacramental” are nothing other than a summary preaching of the promise of the Gospel, which ought to be proclaimed by the minister with force and clarity so that believers may be brought to the end for which the sign was prescribed.
The Word is thus indispensable for salvation, whereas the sacraments are not.
Naturally the next question is: If that is the case then why should we administer the sacraments? Do they become unnecessary if they are not absolutely necessary to our salvation? I will post Marcel’s answer to that question tomorrow.