Sentence:  While 1:1-10 introduces the letter as a whole and not just chapters 1–4, a recollection of the theme of Christ's universal Lordship in the church to <WSD>end off</WSD> the first major unit is fitting and suggests that 4:14-17 is the end of the section. 
Meaning of the word marked with <WSD> tags:  To bring to an end, conclude.