לָ֤מָּה תִשְׁקְלוּ־כֶ֙סֶף֙ בְּֽלוֹא־לֶ֔חֶם וִיגִיעֲכֶ֖ם בְּל֣וֹא לְשָׂבְעָ֑ה שִׁמְע֨וּ שָׁמ֤וֹעַ אֵלַי֙ וְאִכְלוּ־ט֔וֹב וְתִתְעַנַּ֥ג בַּדֶּ֖שֶׁן נַפְשְׁכֶֽם׃
Wherefore do ye spend money for that which is not bread? And your gain for that which satisfieth not? Hearken diligently unto Me, and eat ye that which is good, And let your soul delight itself in fatness.
Read halakhic rulings (Jewish law) on Isaiah 55:2: and classical halakhic sources.