4:9. As was fitting in rhetorical rebuke, Paul uses harsh language: he is not sure that the Galatians “know” God even now. The “elemental things” (NASB) or “principles” (NIV) to which they are returning are presumably the “spirits” (cf. NRSV, TEV) of nature they used to worship as gods (4:8). Foremost among these would be the astral spirits (4:3), associated with special days and seasonal rituals (4:10). 4:10. Judaism had its own special calendar of holy days, new moons, sabbatical years and so forth.