In a parallel move, his party initiated a bill intended to cancel out the effect of the court ruling, and attracted the support of some religious-Zionist politicians in response.
The head of Israel's Reform Movement, Gilad Kariv, referred to Mr Eicher's comments as part of growing "incitement" against his movement.
It comes on the heels of other strongly worded comments about Reform Jews, including the jibe that they are "clowns stabbing the holy Torah", made last month by Mr Eichler's party colleague, Moshe Gafni.
The trigger for the clown comment was clear - it was the state's decision to award non-Orthodox movements a special section at the Western Wall for mixed-gender prayer, which Charedi politicians saw as a public humiliation.
But ritual baths, where people normally immerse privately? Why such an extreme reaction?
The reason is that the end-of-conversion immersion is the point where a person becomes Jewish, and allowing Reform to do this in state facilities seems to them like a step towards state recognition for Reform conversions. It feels - to the Charedim - like a massive blow in that old battle over the question of "who is a Jew?".
For years, Charedi leaders have been likening Reform rabbis to untrained doctors, claiming that, as a fake medic may suggest a phoney cure, Reform rabbis recommend bogus religious practices.
The utter rage over the ritual baths ruling has caused Mr Eichler to change his controversial analogy and demote the Reform rabbi from phoney doctor to self-prescribing mental patient.
