Oplatki are thin square wafers, similar to the bread used for hosts at Mass, but not consecrated. This tradition comes from Eastern Europe, around the area of Poland. The wafers may be embossed with a Christmas manger scene.
Ideally, oplatki are used at the main meal eaten on Christmas Eve. By tradition, the table in the home is set with some straw under the tablecloth to represent the straw in the manger. Children look out for the first star that appears around dusk. This signals the beginning of the Christmas Eve meal. All the members of the family gather around the table. The head of the household may say a prayer of blessing. Then this person begins to distribute the wafer by breaking off a small piece for him/herself. This person offers the remainder of the wafer to the next person, who in turn breaks off his/her piece and shares with the next person.
Alternately, it may be divided in another way. The first person may offer the wafer to the second person, who holds it while the first person breaks off his or her piece. The second person then gives it to the third person who holds it while the second breaks off a piece. The wafer becomes increasingly smaller as it is passed around the table and each person present takes a small piece.
After all present have received a piece of the wafer, a short prayer may be said reminding all of the Incarnation. Then everyone eats their pieces When this is done, the meal itself begins.
The wafer is of the same consistency as the bread used to make hosts for Mass. This is no coincidence. Rather, the oplatki reminds one of the Mass and the bread which will become the Body of Christ. The family around the table is reminded of the community around the altar, the table of the Lord.
As we sit for a common meal, so we are reminded that Jesus gave us the Sacrament of the Eucharist to be food for our souls, the bread from heaven. And the sharing of the one wafer calls to mind unity and reconciliation. It is not unlike the sharing of the sign of peace at Mass. The breaking of the wafer also calls to mind the breaking of the consecrated Host by the priest right before Communion.