The author [of Hebrews] has just said: “let us pay worship to God”; he says now: “Let brotherly love remain” (13,1). Where is the relation? In reality, this very abrupt transition is certainly intended, not only to mark the literary division between the two paragraphs, but also to suggest a profound doctrine about the true way of understanding the worship to be paid to God. Do you want to pay God a worship acceptable to him? Love your brothers! Suggested here by the succession of the two themes, this unexpected connection is expressed very explicitly a little later: “Beneficence and solidarity, do not forget them, for those are the sacrifices that God accepts” (13,16). —A. Vanhoy, A Different Priest: The Epistle to the Hebrews, 403-404.
There’s more of the same to be read in the paragraph and book. Excellent material.