Just as one must prepare nice, clean clothing for Shabbat, so too, one must prepare one’s body for Shabbat. This is part of the mitzva of honoring Shabbat. Thus, the Sages state that it is a mitzva to take a hot bath or shower before Shabbat (Shabbat 25b), because hot water cleans better. One who uses cold or lukewarm water does not fulfill the mitzva (SA 260:1). In the past, when it was difficult to lug water inside in order to wash, the mitzva was limited to washing one’s face, hands, feet, and hair. Those who went above and beyond washed their entire bodies in hot water. But nowadays, when we have showers and electric water boilers, it is a mitzva to wash one’s whole body with hot water. If one normally washes his whole body for a social event, certainly going to greet the Shabbat Queen deserves the same care.
One should not shower or bathe too close to Shabbat, so as to avoid the possibility of unknowingly desecrating Shabbat by turning off the bathroom light or turning off the switch that controls the hot water heater (a common feature in Israeli homes) after Shabbat has already begun. The positive of washing close to Shabbat is outweighed by the risk of desecrating Shabbat.
It is a mitzva for one who needs a haircut to get it on Friday. One who shaves regularly should shave before Shabbat. Similarly, it is a mitzva to cut one’s nails in honor of Shabbat. It is preferable to shave and cut one’s fingernails after midday, because then it is clear that it is being done as part of Shabbat preparations; nevertheless, one may prepare even before midday. One who knows that he will be busy on Friday should cut his hair and nails on Thursday (SA 260:1; AHS 260:6).
The home must also be prepared for Shabbat. It should be cleaned, the table should be set with a nice tablecloth, and the chairs should be neatly arranged around it. One should take care that throughout Shabbat, even between meals, the house and table look nice (SA 262:1). It is also proper to set the table with nice dishes, glasses, and silverware.
Often people think that holiness is expressed only in spiritual activities like Torah study and prayer, while physical needs like eating, sleeping, and beautifying and caring for the body oppose and impede spiritual progress. They think that one should afflict his body, the root of the evil impulse. But then Shabbat arrives and teaches us that it is possible to sanctify the physical. Holiness can be expressed through enjoyable food, nice clothing, and a clean house. Furthermore, perfection is attained specifically when holiness is revealed in all aspects of existence, the spiritual and the physical. Therefore we greet one another with “Shabbat Shalom,” because Shabbat brings peace between the material and the spiritual, and as a result there is peace between husband and wife as well as among people in general (see above, 1:15).
Thus, the Sages inform us:
Two ministering angels accompany one home from the synagogue on Friday night, one good and one wicked. If he arrives home and the candles are lit, the table is set, and the bed is made, the good angel says: “May it be His will that it be this way next Shabbat as well,” and the wicked angel is forced to respond, “Amen.” If this is not the case, the wicked angel says: “May it be His will that it be this way next Shabbat as well,” and the good angel is forced to respond, “Amen.” (Shabbat 119b)
On Shabbat holiness can come to its full expression, in the material and spiritual realms alike. This is why, with the house clean and the table set, even the wicked angel is forced to respond “Amen.” Nevertheless, even if the house is not properly clean, the table not properly set, and the Shabbat food ruined, one must be very careful not to fight or become enraged. Honoring Shabbat requires that the household be at peace, as is stated: “Better a meal of vegetable where there is love than a fattened ox where there is hate” (Mishlei 15:17), and “Better a dry crust with peace than a house full of feasting with strife” (ibid. 17:1). Sefer Ĥasidim elaborates on the former verse:
“Better a meal of vegetable” – on Shabbat, “where there is love” – with his wife and children. “Than a fattened ox where there is hate” – one should not say “I will buy delicacies for Shabbat” knowing full well that he will argue with his wife, parents, or other guests…. This is as it says: “Honor it” (Yeshayahu 58:13) – honor Shabbat by not arguing. (§863)