"The cup of blessing that we bless, is it not a participation in the blood of Christ? The bread that we break, is it not a participation in the body of Christ?"
- 1 Corinthians 10:16
Faith in Christ is a gift of God, and we can believe the gospel only when God gives us a new heart that is open to the preaching of His Word (John 3:5; Eph. 2:8). Of course, everyone who has been given such a heart will finally trust in Christ alone for salvation. There is no way that the Lord can fail to redeem His elect; thus, the elect must believe once the Spirit has regenerated them (John 6:39). Nevertheless, as we have seen, our faith is never perfect before we are glorified. God gives us new, living hearts, but we still have to deal with the fallen tendencies of our fleshly nature, tendencies that cause us to doubt our Father's promises on occasion. There are times when we cry out for God to help us in our unbelief even though we do have real (albeit imperfect) trust in the Savior (Mark 9:24).
In His grace and in His wisdom, God has provided ways by which we can regularly have our faith in His promises fortified. Historically, we have referred to these ways of strengthening our faith as the ordinary means of grace. Prayer, the preaching of the Word, and the sacraments are not elaborate or fancy methods of giving us what we need to confirm our trust in Christ. To an outside observer, they do not seem special at all. After all, they make use of rather common things such as human speech, bread, wine, and water. But by faith and the work of the Spirit, these common elements are used to do an uncommon work — the confirmation of our trust in Jesus and the strengthening of our wills to flee from sin and rest in Christ alone.
Preaching is not a powerless human explanation of the biblical text, for the Spirit accompanies it so that God's Word achieves its purposes (Isa. 55:10–11). Prayer is more than empty words; it establishes communion between us and the Creator, thereby empowering us for belief and faithful, effective service (James 5:16b–18). Baptism and the Lord's Supper are not mere memorials that we do simply because Jesus tells us to do them; rather, we participate mysteriously in Christ Himself when by faith we take part in these ordinances (1 Cor. 10:16).
Question and answer 65 of the Heidelberg Catechism emphasize the role of the sacraments in confirming our faith. They bless us as we receive them in faith, and if we neglect them, we weaken our trust in God's work.
Coram Deo
The sacraments are mysteries in that we cannot explain fully what God accomplishes through them. We do know, however, that they are more than memorial observations. They become effectual means of grace to those with faith by the working of the Holy Spirit (WLC , Q. 161). To downplay their importance is to desupernaturalize our holy religion, so let us have a high view of the sacraments as confirming signs of God's Word.
Passages for Further Study
Numbers 9:1–14
2 Chronicles 30
Acts 19:1–6
Galatians 3:27
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Note: Proper administration of Baptism and Communion can maintain the peace and purity of the church. See, e.g., www.BiblicalPeace.com/PurityPeace