Sexual intercourse during a woman’s menstrual cycle was ruled out in Leviticus 15:19, Leviticus 15:24. Leviticus 15:1–33, however, dealt with various kinds of unintentional contact with things that are unclean. If sexual intercourse was due to an accident in timing, then a period of uncleanness and the subsequent ritual purity were required. Conversely, Leviticus 20:1–27 is set within the context of deliberate sin. Such intentional sin is contrary to the will of God and receives his judgement.
18 Si un homme couche avec une femme qui a son indisposition, et découvre sa nudité, s'il découvre son flux, et qu'elle découvre le flux de son sang, ils seront tous deux retranchés du milieu de leur peuple.