I LOVE the idea of making the sacrament more tied to baptism in a visual way, so I have no problem with the desire to have the young men who administer the sacrament dress in white (and only a shirt is less restrictive than fully white attire). I have a friend who used to think that there was no doctrinal basis for asking those who administer the sacrament to wear a white shirt, but she understood better when I referenced the General Conference talk in which that advice was given and talked a bit about the intended symbolism from that talk.
The doctrinal basis is obvious to anyone who accepts
the possibility of continuing revelation, changing symbolism and/or
apostolic/leadership authority to make a doctrinal basis for new
practices. The case of requesting white shirts be worn in the administration of the sacrament is far less radical a change than going from circumcision to baptism as a sign of accepting God and joining "his people". People might not agree with the doctrinal basis for a practice, but there
absolutely is one - and a very solid one in the case of white shirts and the sacrament.
Having said all of that, I really dislike the idea that there is a "uniform of the Priesthood". I believe linking the sacrament and baptism through visual symbolism
is awesome; extending and distorting that link by applying it to
everything imaginable (even simple church attendance) is planting so
many hedges that the principle gets obscured completely - and, given how
few members even remember the apostolic injunction against extending it
to other things and not making it mandatory even for the sacrament, I
would argue the "uniform of the Priesthood" angle actually has killed
the original beauty of the General Conference explanation of why white
shirts should be worn to administer the sacrament. For too many members, it has become about the shirt instead of the symbolic union of ordinances.
As I said in my response to Anonymous' comment below, I believe we have taken it to such an extreme that we have lost, almost completely, the deep meaning of wearing white for specific things - like *changing* into white for temple ordinances and baptism and wearing white to administer the sacrament. Putting on ("donning") white for those particular things adds symbolic meaning; wearing white all the time for everything church-related lessens that meaning, sometimes to the point of obscuring it completely.
Drag The Halls
42 minutes ago