[4:13] 1 tn Again whether the referent of the phrase ἐν τούτῳ (en toutw) (1) precedes or (2) follows is a problem. This time there are two ὅτι (Joti) clauses which follow. The first is an indirect discourse clause related to γινώσκομεν (ginwskomen) and giving the content of what believers know: “that we reside in him and he in us.” The second ὅτι clause is epexegetical (or explanatory) to the ἐν τούτῳ phrase, explaining how believers know that they reside in God and God remains in them: “in that he has given us of his Spirit.”
[4:13] 2 tn Grk “in him.” Context indicates that the pronoun refers to God (see 4:12).
[4:13] 3 sn The genitive of his Spirit here, like the phrase in 3:24, probably reflects a partitive nuance, so that the author portrays God as ‘apportioning’ his Spirit to individual believers. This leads to the important observation that the author is not particularly interested in emphasizing (1) the ongoing interior witness of the Holy Spirit (which is what the passage is often understood to mean) but is emphasizing (2) the fact that God has given the Spirit to believers, and it is this fact that gives believers assurance of their relationship to God. In other words, it is the fact that the Holy Spirit has been given to believers, rather than the ongoing interior testimony of the Holy Spirit within the believer, which is the primary source of the believer’s assurance.
[4:14] 4 tn Because σωτῆρα (swthra) is the object complement of υἱόν (Juion) in a double accusative construction in 4:14, there is an understood equative verb joining the two, with the resultant meaning “the Father sent the Son to be the Savior of the world.”