Our confession of faith, the Westminster Confession, says that sacraments are given by God in order to confirm our interest in Him.
The word interest does not mean what we would intend if we were to say that we were interested in spiritual things, that is, we wanted to think about them. Rather our interest in Him is the kind of interest that a stockholder has in a corporate—his interest in the corporation is the stake he has in the corporation. The sacraments are immediately given by God in order to confirm our stake in Christ.
Now we as evangelicals often struggle with this because we know, or think that we know, that sacraments do nothing of the kind. We are so accustomed to measure everything by the abuses we see, rather than by what Scripture says, or even what our confession says, that when we read the words that say, “the sacraments are immediately given by God to confirm our interest in Christ,” we take this to mean that the sacraments “are immediately given by God, but not in order to confirm anything at all.”
Of course, a false-hearted and idolatrous abuse of the sacraments does not fool God, not even for a minute. But what is that to you? You are coming in genuine faith, are you not? You are coming with evangelical expectation, is that not true? And this means that God enables you, by faith, to confirm your stake in Christ by this means.
Some might say that if you have the faith, then that is sufficient—you can go off by yourself, you and your faith, and do all your confirming of interest away from God’s people. The bread and wine are entirely optional if faith is sufficient, right? But if God said to meet Him here in the bread and wine, how is it faith to try to meet Him somewhere else? Detaching faith from the instruments God has appointed is neither right nor safe.
Of course we know from Scripture that evangelical faith is the catalyst. When Namaan was told to wash in the Jordan, it would not have been appropriate for him to conclude that another river, or no river at all, would do just as well—even if he recognized that the Jordan was nothing in itself. In the same way, we insist on the potency of faith alone, which means that the faith must do something other than what unbelief would do.
Come, the bread and wine are here. Confirm your interest in Christ by partaking now, together with your brothers and sisters.