This little scene where he burns his father's body, it wasn't originally in the script. But I decided it gave more closure in terms of Luke's relationship to his father, letting go of his father. Even though later on, as we get to the end of the movie, as he joins the Force, he was able to retain his original identity, it's because of Obi-Wan and Yoda, who learnt how to do that: how to join the Force at will and then retain your identity. But it was his identity as he was when he died as Anakin Skywalker.