A sacrament is a “sacred sign,” something visibly manifesting the invisible glory and workings of God. But when we speak of the seven sacraments—sometimes called the “major sacraments” or the “sacraments of the New Law”—we mean more than this.
These sacraments are both signs and causes of grace. As Aquinas puts it, “they effect what they signify.”
In other words, each of the seven sacraments does something: baptism cleanses us of original sin and brings us into the family of God, confirmation confirms our baptism and sends us on mission, the Eucharist gives us the true body and blood of Jesus Christ, confession forgives our sins, matrimony unites us like Christ to his Church, holy orders ordains us to act in the person of Christ, and the anointing of the sick heals us of bodily and especially spiritual ailments. But each of these sacraments uses visible signs so that we can better know and believe what’s invisibly occurring.
The sacraments are best understood as a continuation of the Incarnation. God has always been infinitely powerful and glorious, but fallen man struggled at an invisible God, quickly falling into idolatry. The Incarnation is, in part, a remedy for this human weakness. Jesus, as “the image of the invisible God” and the Incarnate Word, makes the invisible and infinite majesty of God present in a tangible, visible form.
Christ ascended into heaven but left behind the Church as a continuation of his bodily incarnation, which is why St. Paul speaks of the Church as the “Body of Christ” and of it being built up into “the measure of the stature of the fulness of Christ” and growing “up in every way into him who is the head, into Christ” (Eph. 4:12-13, 16). In the Incarnation, God the Son forever united himself to materiality by taking on a human body. He continues this union through the Church and through the sacraments.
The sacraments are foreshadowed throughout the Old Testament. One particularly elucidating example is the washing of Naaman the Syrian in 2 Kings 5. A leper and a Gentile, Naaman comes to the prophet Elisha for healing, and Elisha sends him to “wash in the Jordan seven times, and your flesh shall be restored, and you shall be clean” (2 Kings 5:10). The banality of the proposed gesture angers Naaman, but is persuaded to obey; he dips “himself seven times in the Jordan, according to the word of the man of God; and his flesh was restored like the flesh of a little child, and he was clean” (2 Kings 5:14).
In the ordinary course of nature, such washing is good only for the “removal of dirt from the body” (1 Pet. 3:21), but when done “according to the word of the man of God,” it leads to miraculous healing and spiritual cleansing (ultimately, leading Naaman to faith). There’s a correspondence between the sign and the action. God could have healed Naaman by having him dip into mud, but he chooses to do so in a way that the action signifies what it causes.
The role of the sacramental minister is clear from the first few chapters of the Gospel of John. The first of Jesus’ public miracles is the turning of six jars of water into wine, yet he does this entirely through mediators. His mother approaches, mentioning the lack of wine. She then says to the servants, “Do whatever he tells you” (John 2:5). Jesus instructs the servants, without ever touching the jars himself. Nevertheless, the miraculous action is attributable to Christ via these ministers: “this, the first of his signs, Jesus did at Cana in Galilee, and manifested his glory; and his disciples believed in him” (John 2:11).
Jesus’ miracles frequently work in this way: he works through others, and/or through physical objects. In the next chapter of John, we read that “Jesus and his disciples went into the land of Judea; there he remained with them and baptized” (John 3:23), but John later clarifies that while “Jesus was making and baptizing more disciples than John,” “Jesus himself did not baptize, but only his disciples” (John 4:1-2). As with the wedding feast of Cana, Jesus is working his miracles through others, who are instructed to “do whatever he tells you.” As St. Augustine points out, whether you were baptized by Paul, or Peter, or Judas, you were ultimately baptized by Christ.