The movie is an allegory for the parable of the Prodigal Son in The Four Gospels.
A parallel of a parable, if you will. (Or an allegory of a story.) Fred Rogers was an ordained Presbyterian pastor, and the film even alludes to this by mentioning that he reads Scripture in his free time. With that said, it seems possible for there to be some Biblical parallels. Lloyd represents the Prodigal Son, running away from his father, only to patch things up with him in the end. It should be noted that the Prodigal Son did not leave home simply because he wanted to see the world. He deliberately rejected a relationship with his father
, much like Lloyd. The Prodigal Son only cared about making a name for himself. This is best shown in the movie when Lloyd leaves his father in the hospital, without a hint of empathy, to get back to work. But when Lloyd finally talks things out with his father near the end, Lloyd realizes that his father wants to mend their broken relationship too. This is similar to the Prodigal Son's father welcoming him with open arms.