Although this gospel reads as if it was a piece of prose there is a lot of depth contained in it.
In the first paragraph, Luke describes the curing of Peter's mother-in-law. Note that Luke says "he rebukes the fever," not that he cures her. Luke is showing that Jesus has dominion over all of nature.
In the next paragraph all the people come to him. He heals them and casts out demons who recognise him as Lord. Again, Luke is showing the dominion of the Lord over the spiritual world.
In the last paragraph Jesus says that he must go out and proclaim the good news everywhere. This message is for everyone, starting in Judea and spreading out till eventually the whole world heres of it.