Anyone looked at this verse? There are several things to ponder:-
# What does "spirit" connote in the phrase, "spirit which dwells in us"? The term only occurs in one other place in the Epistle, namely, at 2:26.
# What is the subject of the quotation in verse 5? God? or spirit? If so, in what sense might "spirit" be taken (see first point)? Is the spirit God's spirit? Since "pneuma" is either nominative or accusative, could "spirit" be the object?
# Which rendering of "dwell" should be preferred (there are two Greek variants of the verb), namely, "(God) made to dwell" or "(the spirit) took up residence?"
# Does "scripture says," introduce the citation which then extends to the end of v.5 followed by another (identifiable) citation in v.6 or (since the quotation in v.5 is unidentifiable) might we take v.5 as a parenthetical comment translating, "Do you think that Scripture speaks in vain? Does the spirit that God made to dwell in us desire enviously?"
# Whence the citation?
Here are some translations:-
"The spirit He caused to live in us envies intensely" (NIV, NEB)
"He jealously desires the Spirit which He has made to dwell in us" (NASB) or "He jealously desires the [human] spirit which lives in us"
"The Spirit who dwells in us yearns jealously"(NKJ) or "the Spirit of God in us loathes envy" (Richard Bauckham)