In my opinion, the waiting period that exists in countries that honor temple sealings as legitimate marriages grew out of an understandable desire to make sure of three things:
1) Unmarried couples who found out they were pregnant couldn't get married in the temple. That is more of a "punishment" mode, but I understand totally the idea of a "grace period" for repentance ("change of priority" in this case) to occur.
2) People who had no real testimony and commitment to the Church and/or the Gospel couldn't convert then get married in the temple immediately just to please a potential spouse. That is more of a "slow down the hormones" mode, and I understand that idea completely and have no problem with it whatsoever.
3) New converts couldn't make the covenants that are central to the ceremony without adequate time to understand them properly. That's more of a "protection" mode, and I also understand that idea and have no problem with it whatsoever.
I have no real issues with those general concepts and concerns, but I agree with many who believe that these restrictions shouldn't play a role in situations where otherwise worthy, mature and knowledgeable members are involved. I would love to see the rules relaxed to allow for a reasonable time frame between a civil marriage first and a temple sealing next anywhere in the world - say, a week or even a month to give time to travel to a temple, since that time frame is necessary in some situations. I also would love to see an open allowance (or even encouragement) of a civil ceremony following a temple sealing, if the desired emphasis needs to remain on the sealing being the "primary and original" ceremony. I understand that concern, and I have no real problem with it - but I also see no problem in a civil ceremony that does not imply in any way that the previous temple sealing was not "valid" as a marriage.
We allow couples to "renew their vows" without much concern, even if that is a bit unorthodox within Mormonism. Doing so a few days or weeks after the sealing, especially in order to include non-member family in a ceremony in which they can participate, really isn't any different at its core than doing it after 20 or 50 years.
Finally, since many countries require a civil ceremony to certify that a marriage is accepted by the government (and don't accept a temple sealing as acceptable on its own), and since members in those countries are allowed to marry civilly and then be sealed in the temple as quickly as is possible following the civil ceremony, I would have no problem allowing those same arrangements to apply in the United States - and anywhere else the waiting period currently exists.
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