Number 6:13-20 outlines a ceremony, including a purification offering (vv. 14, 16), to be performed at the end of a successfully completed Nazirite period. The purpose of this mandatory purification offering constitutes a crux. For what nondefiant sin or sever physical ritual impurity- the evils remedied by non-calendric purification offerings elsewhere (e.g. Lev 4:1- 5:13; 12:6-8; 14:19)- could such a sacrifice expiate in this context? The answer to this question may affect or at least test our understasnding of purification offerings in general.