Albert Barnes Commentary Jeremiah 35:14

"The words of Jonadab the son of Rechab, that he commanded his sons, not to drink wine, are performed; and unto this day they drink none, for they obey their father`s commandment: but I have spoken unto you, rising up early and speaking; and ye have not hearkened unto me." — Jeremiah 35:14 (ASV)

Are performed – Are established, that is, are maintained in full force.

To this day – that is, for more than 200 years.