3:3 The true sign of a right relation to God is not the observance of an external rite but a manifestation of the three characteristics mentioned. Worship God in the Spirit not only refers to one’s being alive in the spirit (John 4:24) and thereby qualified for living worship, but also includes the Holy Spirit’s enablement in expanded worship expressions in song (Ephesians 5:18, 19), in prayer and singing (I Corinthians 14:15) and in communion with God (I Corinthians 14:1, 2).

The cross-reference for this passage is Deuteronomy 30:6, "And the Lord your God will circumcise your heart and the heart of your descendants, to love the Lord your God with all your heart and with all your soul, that you might live." The footnotes hear say, "…circumcise their heart (v. 6), a reference to the messianic covenant when God would deal with man’s spiritual problem through an internal transformation."

Circumcision is a cutting away of unnecessary flesh that gets in the way. We, as believers, desire for God to "cut away" any of our flesh that would get in the way of what He desires to reproduce in and through us.