This week we will be observing the Lord’s Supper at Trinity. This sacrament has been given to us to strengthen our faith, to remind us of Christ and what he has done for us, and, as our catechism puts it, to give those who partake worthily “not after a corporal and carnal manner, but by faith…[Christ’s] body and blood, with all his benefits, to their spiritual nourishment and growth in grace.” You may wonder, though, how can someone “grow in grace”? Don’t we already have the fullness of the grace of God when we believe the gospel? Well, the answer is, yes! We do have the fullness of God’s grace when we trust in Christ for the forgiveness of our sins. Yet our faith must be continually strengthened and built up. Calvin put it this way, “It is by no means sufficient that faith is once begun in us. It must be nourished continually, and increase more and more every day. To nourish, strengthen, and advance it, the Lord instituted the sacraments.”
God knows that we are all prone to walk by sight and not by faith. That’s why he gives us the sacraments, “sensible signs” showing us that the promises of the gospel are as sure, as real as the bread and the cup that we hold in our hands, as real as the water in which we were baptized. As you go about your week, I want to encourage you to prepare your heart to receive the sacrament of the Lord’s Supper this coming Sunday. And, just in case anyone is curious how exactly to do that, the Westminster Larger Catechism just happens to have a question and answer devoted to that very topic, question 171
Q. How are they that receive the sacrament of the Lord’s supper to prepare themselves before they come unto it?
A. They that receive the sacrament of the Lord’s supper are, before they come, to prepare themselves thereunto, by examining themselves of their being in Christ, of their sins and wants; of the truth and measure of their knowledge, faith, repentance; love to God and the brethren, charity to all men, forgiving those that have done them wrong; of their desires after Christ, and of their new obedience; and by renewing the exercise of these graces, by serious meditation, and fervent prayer.
So take the Larger Catechism’s advice and prepare your hearts. You don’t have to tackle everything mentioned in the answer all at once. Just take one thing, perhaps you could start with examining yourself as to whether you’ve “forgiving those that have done [you] wrong,” or you could confess your “sins and wants (failings in going the good God’s law requires).” The Larger Catechism has given us a rubric, a guide for preparing our hearts to receive the sacrament. Let’s take advantage of it and enter into the observance of this sacrament with the proper reverence, knowing that, in this sacrament, Christ’s body and blood, “are spiritually present to the faith of the receiver, no less truly and really than the elements themselves are to their outward senses; so they that worthily communicate in the sacrament of the Lord’s supper, do therein feed upon the body and blood of Christ, not after a corporal and carnal, but in a spiritual manner; yet truly and really, while by faith they receive and apply unto themselves Christ crucified, and all the benefits of his death.” So prepare your hearts knowing that’s what we’re participating in this Sunday.
 WSC Q. 96
 Geneva Catechism Q. 316
 WSC Q. 92
 WLC Q. 171
 WLC Q. 170