Verses 8-10 discuss the pre-eminence of love, concluding with the statement: Love does no harm to its neighbor. Therefore love is the fulfillment of the law.
Verses 11-14 discuss the imminent return of Christ, and the effect that return should have on our lives. While many see a focus on Christ’ return as somewhat “pie in the sky,” Paul saw that focus as having a very practical effect, changing our behavior in almost every way. It is because of this imminent return that we do not live as others do (which reminds us of Romans 12:2). We do not focus on human desires but “behave decently.” We are to be clothed in armor of light, putting on the Lord Jesus Christ.
These last two sections in the chapter echo the instructions given in Romans 12, reminding us that this section is a unit. We should not rip Romans 13:1-7 out of this context, as if it were a tract someone found and inserted into the book of Romans. As we interpret these 7 verses, we must do so in a way that is concordant with the previous chapter and with the remainder of chapter 13.