Sabbath and the Lord's Day
There is a Jewish legend about how Sabbath came to be the Holy day, which explains that all the days of the week got paired off, and Saturday was left remaining without a partner. It complained to God, who said, "Fear not, the people of Israel will be your partner." The Sabbath has served as a model for the Christian's Sunday. 

Saturday and Sunday make up the holy days for Jews and Christians, Saturday or Sabbath is the rest day of the Jews. On this day they are not allowed to work, this is clearly stated in the fourth commandment:

"Remember to keep the Sabbath day holy. You have six days to labour and do all your work. But the seventh day is a Sabbath of the Lord your God that day you shall not do any work."

(Exodus 20:8-11)

Sabbath means 'to cease' or 'to break off' from work, it begins on Friday evening at sunset and ends at night fall on Saturday. To the Christians Sunday or the Lords day is the holy of the week. This is because Jesus was crucified on Sabbath but he rose from the dead the day after Sabbath, and according to Apostles this will be the day he will appear to us at the end.

On Sabbath and the Lord's day Jews and Christians dress up in their best clothing to go to the synagogue or church to pray and listen to mass. In both religions this day (Sabbath or the Lord's day) is a time for rest when one should stop worrying about work, in Judaism this is taken quite seriously. All the housework is done in advance, the food is prepared  so there is no work to be done on this day. These two days, the Sabbath and the Lord’s day gives people a holiday, a time of peace and quiet to spend with the family or close friends.