How do we know that a person should change his clothes to serve Hashem? The Torah writes, “A kohen should take off his bigdei kehunah (clothing worn specially for service in the Beis Hamikdash) and put on different clothes [to clean the ashes from the altar]” (Vayikra 6). From here we learn that a person “should not serve wine to his master in the same clothes that he wore while cooking for his master” (Shabbos 114a).
Halachic authorities apply this rule to someone who wears work clothes. Painters and plumbers generally have special on-the-job clothing. Since one would generally not meet with an important person dressed in these clothes, he should try to make time for changing his clothes and washing before praying (Kaf Hachaim 98,29).
Policemen and soldiers wear special clothing while they work. These uniforms are not merely work clothes; rather, they help identify the person’s affiliation and profession. Wearing such clothing is considered dignified even when standing before Hashem, and one may pray in them. However, doctors or surgeons, who have a special robe that they only wear while in the hospital, should preferably change them for tefillah (heard from Rav Moshe Sternbuch).
Today, in most parts of the civilized world, people wear socks and shoes, and one should not recite Shemoneh Esrei without them. Even wearing socks without shoes is problematic, with the exception of Yom Kippur and Tishah B’Av, when one is forbidden to wear shoes (Aruch Hashulchan 91,5). The same is true about wearing sandals without socks where one’s ankles are exposed (Mishnah Berurah 91,12).
Wearing slippers to pray depends on whether one would wear them outside of the house. If they are respectable and clean, and one would greet important guests in his home in his slippers and would wear them outside as well, then one may wear them for tefillah. However, if a person would be embarrassed to be seen outside in his slippers, he should not wear them for tefillah (Responsa Shevet Hakahasi 3,41).
There are many different types of popular footwear today, some stylish and others resembling slippers and beachwear. Each person must consider if he would feel comfortable standing in front of a distinguished person wearing his shoes. If he would not, then he should wear different shoes when reciting Shemoneh Esrei.
Text Copyright © 2012 by Rabbi Daniel Travis and Torah.org