The Hebrew verb bagad means to act treacherously, to deal deceitfully, or to be faithless — especially within a covenant relationship. It describes the betrayal of trust, whether in marriage, friendship, or the covenant with God.
Bagad appears frequently in the prophets to describe Israel's spiritual adultery — her betrayal of the covenant with YHWH. Malachi uses it to denounce both marital unfaithfulness and covenant treachery. The word carries deep relational weight: it is not mere wrongdoing but the violation of a sacred bond of loyalty.
Theologically, bagad exposes the gravity of covenant unfaithfulness. Every act of treachery against a spouse, a friend, or God is a bagad — and the prophets consistently call Israel to repentance for this sin.