Since we are a congregation of The Lutheran Church-Missouri Synod, we follow the teaching and practice of the Lutheran Church with regard to Holy Communion. We joyfully confess the Word of Jesus (Matthew 26:26-28; Mark 14:22-26; Luke 22:14-23; 1 Corinthians 11:23-26), that everyone who eats the bread and wine also eats Jesus' true and holy Body and Blood--the same Body and Blood that Jesus had in the womb of Mary, in which He lived, was crucified, raised from the dead, ascended to the right hand of God the Father, and in which we will see Him when He comes in glory to judge the living and the dead.
Everyone who eats and drinks the Supper–even if the person does not believe–receives bread, wine, Body, and Blood. For this reason, we take very seriously every person's participation in the Sacrament at our altar. To encounter without faith the Jesus who is present in the Supper is a fearful thing--as fearful as encountering Jesus without faith at any moment.
Since we believe that the Lord's Supper is both a confession of faith in the Words of Jesus--that He is truly present where He says He will be--as well as a confession of the unity granted by the Holy Spirit in those same words, we look for two things before we join together at the altar.
First is simply faith in the Words of Jesus. We confess that we eat and drink Jesus' true Body and Blood under bread and wine, as He says. Whoever believes those words--Body and Blood, given and shed for you for the forgiveness of sins--has in the Supper what they say.
Second is the public confession of unity (see, for example, 1 Corinthians 10:15-17). If someone desires to share this Holy Supper with us, where does that person currently receive Communion? Because neither the pastor nor anyone else knows--or can know--an individual's heart, the public confession can only be seen by where a person communes. If a person communes in a church with which the LCMS is not currently in altar and pulpit fellowship, then that person is not yet (or no longer) in fellowship with us. Because the Sacrament is a visible, public sign of unity in confession, such an individual would want to understand and confess what we teach and believe prior to receiving the Supper at our altar. Conversely, if a person receives the Supper at our altar, by definition that person enters fellowship with us and has severed fellowship with any congregation of a different confession with which we are not in fellowship. In other words, communion fellowship equals church fellowship, and vice-versa.
We want you to know what you are confessing when you receive the Lord's Supper at our altar, and to be able to confess that unity with full knowledge and joy. For this reason we ask that, prior to communing, you speak to the pastor and if you are not already a member of a congregation in fellowship with us, he would be happy to talk with you about receiving the Supper at our altar in the future.
You may also want to look at the following resources for more information:
Joel D. Biermann, "Step Up To the Altar: Thinking about the Theology and Practice of the Lord's Supper."
The LCMS Commission on Theology and Church Relations, "Admission to the Lord's Supper: Basics of Biblical and Confessional Teaching."
And for a more in-depth discussion of the practice of the Church throughout time, see Werner Elert's book Eucharist and Church Fellowship in the First Four Centuries, which shows that our practice follows the universal practice of the early Church.