Usually, I would advise people using the Pro-summer line (60D, 7D) or the Pro full frame for wedding photography, reason being that you will need a camera with a really good high ISO to counter noise reductions for different lighting situation as well as a better censor plate. That being said, there is nothing wrong with using a T line camera because it is not the equipment but the photographer line.

To answer your question, I would advise you to seek out photographic equipment company that offer rental and try out different lenses before you commit to make a big purchase. Generally, a 50mm f/1.4 on a crop frame is a pretty good walk around lens, but it is not the best choice in wedding photography. Try a 85mm for portrait, or rent the L lens 24-70 for better performance.

I would also advise you to look into flash photography because there is nothing more important than the relationship between external lights enhancement and the low light venue.

Vivian