Hosea 13:12

The iniquity of Ephraim is bound up; his sin is hid.

Ephraim's iniquity is bound together and kept in reserve rather than forgiven and taken away. His sin remains hidden in the sense of being concealed and retained, not removed by pardon and cleansing. It is treasured up against him, held fast instead of being blotted out. In its setting of approaching judgment this stored-up guilt carries a solemn warning that ruin must follow. Unless the people turn back to the Lord, the iniquity so retained will break upon them in destruction.