After baptism (which often takes place during the Divine Liturgy, or eucharistic service), the child is ready to partake of the Sacrament of the Eucharist for the first time. The Eucharist is the central and most important sacrament of the Christian faith. This is the sacrament (also known as "Communion" or the "Lord's Supper") instituted by Christ at His Last Supper with His disciples, when He commanded them to participage in His life by partaking of the bread that is His Body and the wine that is His Blood.

The Eucharist in the Orthodox faith is no mere symbol or commemoration; it is a genuine partaking in the life of Christ. While Orthodox do not subscribe to the Roman Catholic doctrine of transubstantiation, which asserts that the bread and wine are physically, chemically changed into Christ's Body and Blood, we do believe that the bread and wine are spiritually, mystically changed in a way that we cannot begin to understand. The early Church Fathers simply proclaimed this miricle, "O great Mystery." The bread and wine do indeed become the Body and Blood of Christ within the believer, strengthening and empowering him for the Christian life and gradually, over the years of his life, helping to transform him into the image of Christ. The Eucharist is often referred to as "the medicine of immortality" because without it, we cannot attain eternal life.

The newly baptized infant is sinless (as also is a newly baptized adult-all sins are washed away in baptism). But as he grows, sin inevitably enters his life, and he needs to be cleansed of that sin in order to restore the purity of his baptism. This cleansing is accomplished through the Sacrament of Confession. In the Orthodox faith, the believer confesses his sins privately to a priest, who listens, perhaps offers counsel, and in some cases may impose a penance (usually in the form of a period of abstinence from the Eucharist). He then pronounces God's forgiveness of the sins confessed (called "absolution"). Thus the believer is assured that those particular sins will never come back to haunt him, in this life or at the judgment: they are wiped off his slate in the sight of God forever.

Believers are encouraged to confess regularly. In some traditions, confession is required each time the believer wishes to partake of the Eucharist. At St. Lawrence, however, frequent communion is encouraged, and confession is not a formal requirement on every occasion.

Confession and the Eucharist provide for the believer's spiritual health, but the Church does not neglect his physical health. The Sacrament of Holy Unction (or anointing with holy oil) has a variety of purposes, but it is primarily intended for the healing of physical illness. This sacrament is performed for individuals at need (including, but not limited to, when death is near), and also for the Church as a whole at certain set times, such as Wednesday of Holy Week.