A farewell to the deceased is his final "commendation to God" by the Church. It is "the last farewell by which the Christian community greets one of its members before his body is brought to its tomb." The Byzantine tradition expresses this by the kiss of farewell to the deceased:
By this final greeting "we sing for his departure from this life and separation from us, but also because there is a communion and a reunion. For even dead, we are not at all separated from one another, because we all run the same course and we will find one another again in the same place. We shall never be separated, for we live for Christ, and now we are united with Christ as we go toward him . . . We shall all be together in Christ."
Source: Catechism of the Catholic Church (Vatican.va)