Charles Ellicott Commentary Hosea 5:7

"They have dealt treacherously against Jehovah; for they have borne strange children: now shall the new moon devour them with their fields." — Hosea 5:7 (ASV)

Strange children refers to offspring that followed in the ways of their mother . This also refers to the consequences of intermarriage with pagans.

The “month” may be a personification of the period of a month (Henderson), during which the now closely impending (perhaps already commenced) invasion by Tiglathpileser takes place (2 Kings 15:29; 2 Kings 2:0). This invasion was due in part to Ahaz having sought the aid of Assyria against Pekah and Rezin.