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Source:Joseph Fielding Smith:Conference Report:1941:that marriage while they are in the world, yet the fact remains that when they are dead the marriage comes to an end
Joseph Fielding Smith (1941): While the Church, as well as the world, would recognize that marriage while they are in the world, yet the fact remains that when they are dead the marriage comes to an end
Joseph Fielding Smith:
While the Church, as well as the world, would recognize that marriage while they are in the world, yet the fact remains that when they are dead the marriage comes to an end.
Therefore when they are out of the world they neither marry nor are given in marriage; but are appointed angels in heaven; which angels are ministering servants, to minister for those who are worthy of a far more, and an exceeding and an eternal weight of glory.
I take it that this has reference to those who have been just and honest and have been willing to keep other covenants and commandments the Lord has given them. They are members of the Church, but have not been willing to enter into this great and crowning covenant, if you please, which would exalt them to be the sons and daughters of God. And therefore, as I read further:
For these angels did not abide my law; therefore, they cannot be enlarged, but remain separately and singly, without exaltation, in their saved condition, to all eternity; and from henceforth are not gods, but are angels of God forever and ever.
Forever and ever! Think of it! It fills my heart with sadness when I see in the paper the name of a daughter or a son of members of this Church, and discover that she or he is going to have a ceremony and be married outside of the Temple of the Lord, because I realize what it means, that they are cutting themselves off from exaltation in the Kingdom of God.Now, again, the Lord continues, in this revelation, to say that if they are married by His word, then they shall pass on to the exaltation, and that exaltation is a fulness and a continuation of the seeds forever. In other words, the family organization is intact throughout all eternity and there shall be eternal increase,--and that is the crowning glory, if you please, in the Kingdom of God. 
- Conference Report (April 1941), 37-38.