Boruch Hamavdil
35. One may not do any melochoh before Havdoloh. After saying Havdoloh in Shmoneh Esrei, one may do melochoh even if he has not said Havdoloh with a cup of wine (שו"ע סי' רצ"ט ס"י). If one needs to do melochoh before saying Havdoloh in Shmoneh Esrei, he should say “ברוך המבדיל בין קודש לחול” without a brochoh and then do melochoh (שם).
36. Which melochos are ossur. Some poskim hold only full-fledged melochos, such as writing [koseiv] or weaving [oreig], are ossur, but carrying from one reshus to another or lighting a candle, which does not take effort, is not ossur (רבינו ירוחם הובא ברמ"א).
37. Most poskim, however, hold all melochos are ossur (כל בו, רמ"א שם), including melochos derabonon (מ"ב סק"ל), at least until one says “Boruch Hamavdil.” Accordingly, the one who lights the Havdoloh candle should say “Boruch Hamavdil” if he did not say Havdoloh in Shmoneh Esrei beforehand.
38. “Shavua tov,” “A gutte voch.” One is not yotzei his chiyuv of Havdoloh to allow him to do melochoh by saying “Shavua tov” or “A gutte voch” since those phrases do not contain any mention of distinguishing kodesh from chol (חוט שני ח"ד פפ"ה ססק"א, הגר"נ קרליץ).
39. “Gott fun Avrohom.” Some poskim say that reciting the tefilloh, ‘Gott Fun Avrohom’, is like saying Havdoloh and allows one to do melochoh (שו"ת קנין תורה ח"א סוף סי' פ"ט). Others disagree since the idea of havdoloh – distinguishing – is not mentioned in it (שו"ת מגדנות אליהו ח"ב סי' י"ח).
40. Women. Women may not do melochoh before saying Havdoloh either. Therefore, women should say out loud “Boruch Hamavdil bein kodesh lechol” before doing any melochoh on Motzei Shabbos (רמ"א).
41. Did melochoh before Havdoloh. If one davened Maariv without saying Havdoloh in Shmoneh Esrei or Boruch Hamavdil, and, without thinking, did melochoh before saying Havdoloh with a cup of wine, he does not need to daven Maariv again (ביאה"ל סי' רצ"ד ד"ה ואם טעה). This case cannot be compared to the above halochoh (20) about eating before saying any form of Havdoloh.
