I thought it was very interesting that TFA did not show us Luke speaking or taking his light saber from Rey when she extends it to him. I suspect that the movies are going to try to keep us in suspense in terms of whether or not Luke will join the fight. I am guessing that initially, Luke will refuse and claim non-interference in the affairs of the galaxy but then realize that he must get involved. I also fully expect to see an epic light saber duel between Luke Skywalker, going full Jedi, and Emperor Snokes, who will be revealed to be a some super powerful sith lord that only Luke has a chance of stopping. I also fully expect to see Luke training Rey and then she takes on a fully trained Kylo Ren in another epic light saber duel.