Marriage is a natural institution that predates the Church and all other human institutions. In the beginning, God made them male and female, and the two became one flesh. Within the Church, for the members of the Church, Christ endowed that natural institution with the supernatural grace of a Sacrament, but in doing so He did not thereby abolish the natural institution that is “the one blessing not forfeited by original sin nor washed away by the flood”. It is impossible for one who is not baptized to receive any other Sacraments, but a marriage is logically first valid in the natural order and then endowed with sacramental grace. When two Christians marry, these two things happen at the same time, but when both spouses are not baptized, the natural union occurs but the sacramental grace is not poured out upon the union unless and until both spouses submit to baptism.