ISA 58:13

13 If thou turn away thy regel on account of Shabbos, from doing thy chefetz on My Yom Kodesh; and call Shabbos an Oneg [(Delight)], the Kedosh Hashem[(Holy Day of ]Hashem[)], “honored”; and if thou shalt honor it, not doing thine darkhim nor finding thine own chefetz, nor speaking [worldly] words: