The Torah in Parashat Behukotai (Vayikra 27:28) addresses the case of “Herem” – where a person declares a possession consecrated, but without specifying that it should be consecrated for the Bet Ha’mikdash. The object or property in question is given to the Kohanim serving that week in the Bet Ha’mikdash. The Torah commands “Lo Yimacher” – that the owner is not permitted to sell the item, as it must be given to the Kohanim.
Once the consecrated item is given to the Kohen, the Kohen may use it however he wishes; it is not considered sacred after the Kohen receives it. If it is land, and the Kohen sells it, the property returns to the Kohen on the Yobel (jubilee year).
The Sefer Ha’hinuch makes no mention of Malkut being administered to a violator who transgresses this prohibition by selling property declared Herem. It appears that the Sefer Ha’hinuch follows the view taken by the Rambam, in Hilchot Bechorot (6:8), that one is not liable to Malkut for violating this prohibition. We might have assumed that a violator would be liable to Malkut, since this command is transgressed by performing an action – specifically, making a legal transaction, which normally entails some sort of action. Perhaps, the Rambam felt that this violation is not punishable by Malkut because the transaction does not take effect. Since the Torah forbade selling this property, the sale is not valid and is legally ineffectual. For this reason, perhaps, the act of transaction is not significant enough to warrant Malkut.
The Torah in this verse also adds a second command – “Lo Yiga’el,” forbidding the redemption of property which one has declared Herem. Normally, when one consecrates his possession for Bedek Ha’bayit (the treasury of the Bet Ha’mikdash), he transfers its sanctity onto a sum of money equaling the value of the property in question, and then the money is given to Bedek Ha’bayit while the property becomes permissible for use. The Torah commands that in the case of “Herem,” this may not be done. Rather, the item must be given to the Kohanim. In regard to this Misva, too, the Sefer Ha’hinuch appears to maintain that one is not liable to Malkut, likely for the same reason discussed above – because the redemption is ineffective, and thus nothing has been done through the act of redeeming the property.
The Rambam maintains that these prohibitions apply even nowadays in regard to land outside Israel (land in Israel can be declared Herem only when the laws of Yobel apply), and to moveable items in all locations. If someone were to declare such property Herem, even nowadays, it would be forbidden to sell or redeem the property.