The Christian 'week' is derived from the Jewish observance of the Sabbath Day which as you point out is Saturday. The idea of a day of rest dedicated specifically to God was taken over by Christians but was transferred from the Jewish Saturday to the 1st day of the week, Sunday, in honour of the Resurrection of Christ, and because Saturday is reserved for Mary the mother of Christ. The reason can be found in Acts 20:7 or I Corinthians 16:2 in the Bible. Other notable day changes include the Jewish fasting days of Tuesday and Thursday. These were translated by Christians to Wednesday (the day Judas betrayed Jesus) and Friday (the Crucifiction). This was because Thursday is a Christian day of celebration (Jesus' Ascension, and the Last Supper). In brief, here are the Christian days: Sunday - celebrate the Resurrection of Jesus Monday - Holy Souls departed Tuesday - Holy Angels Wednesday - All Saints Thursday - Holy Eucharist Friday - Holy Cross Saturday - Virgin Mary Hope this helps.

The Jews did observe Saturday (although they didn't call it Saturday - i.e. Saturn's Day - our days of the week are Roman). In fact, while our calendar system of today has the day changing from one to the next at midnight, this wasn't the case originally. So originally, Jews and early Christians observed the Sabbath as sundown Friday until sundown on Saturday. This changed to Sunday when Constantine was the Emperor of the Roman Empire, and his Christian population was growing. He himself apparently converted, and the Council of Nicaea was called. Prior to this, Christians would be eaten by lions at the coliseum, or tortured and killed in other horrendous ways. One way was crucifixion. There was also up-side-down crucifixion, and other insanely evil and creative ways of killing people. At the time when the Council drew near, their society was beginning to change. The non-Christians had their "day off" from work and their wild parties on Sundays, which was the esteemed day of the Sun god, while Christians had their "day off" on their Sabbath, from sundown Friday until sundown Saturday. This was an annoying problem that got in the way. Also, the Christians had their own Festivals of the day such as the Passover, while the non-Christians/pagans celebrated the Festival of Ishtar (present day Easter) and other holidays like Christmas, where they adorned trees with decorations and had orgies and gifts at the trees. All these differences were "reconciled" at the Council of Nicaea. Constantine had "converted" and declared Christianity the official religion, but the existing Christian Festivals such as the Passover were axed and replaced by newly Christianized pagan holidays such as Christmas and Easter. The church clergy of the day that attended the Council (which took place around 322 A.D., about three centuries into Christianity) received their power in exchange, and the very politcally powerful Roman Catholic Church was born. It was well over a millenium later and after many well-meaning Christians had been burned at the stake as "heretics" for trying to educate the common people about the REAL truths of their own religion that protestant churches finally began to form and allow regular people to read the Bible.

Sunday is considered the Sabbath in the wider sense of a day of rest, which is what the Hebrew word comes from. The earliest Christians were Jewish converts and others who lived close proximity to the Jewish lands of the Roman Empire; they observed the Jewish Sabbath and also kept the following day sacred in memory of Jesus' resurrection.

Sunday is the Lord's day, the first day of the week in which Jesus rose from the dead. Saturday was the Sabbath day which God commanded His chosen people the Jews to observe as a holy day of rest unto Him, the LORD their God. I personally believe that the Lord Jesus Christ died on Wednsday, not Friday, and rose on Sunday(which would be 3 days according to the Jewish days in the Scriptures, which began at evening and ending at morning--see Genesis Ch.1 where the days go by as "the evening and the morning were the first day, the evening and the morning were the second day, etc.--thus, Christ would have been dead for three Jewish days from Wednsday evening to Sunday morning and He rose on Sunday morning.) I hope that this helps. -In the Master's service. Thank you and God bless you!

The Bible Sabbath did not change, just as the other commandments of the Ten Commandments of God did not change. God wrote them with his finger on two tables of stone (the 18th verse of the 31st chapter of Exodus). Jesus did not change the Sabbath, and neither did His Father (God) change it. "For the Son of man is Lord even of the sabbath day" (the eighth verse of the 12th chapter of Matthew). Only Constantine cause the change, since he cause the union of pagans with so-called "Christians." On a side note, the word "Sabbath" in many languages is similar to the word for Saturday in many languages. In Spanish the same word, "sabbado" means Saturday. It also means "sabbath." The Jews were not the only people who God commanded to observation of the Sabbath. He was not a respecter of persons (the 34th verse of the 10th chapter of Acts). He spoke to all humans that commandment as with the other commandments, such as "thou shalt not kill." That's for every one, not just Jews. http://www.gotquestions.org/Constantine-Sabbath.html

It was converted to paganism when the heathens changed the calendar. Pagans(Roman Empire Religion) worships the sun god, Amun-Ra, on Sunday. It goes along with the changing of God's true start of the day, which is when the sun rises, not in the middle of the night (12:00am) like it is today. You must seek God's truth which is in the holy bible and you will see who has control of this world(for now).

Saturday is still the Sabbath, but for Christians the command of keeping the Sabbath is fulfilled through having faith in Jesus. I've researched this a lot... You may want to skim over Colossians 2:16; Romans 14:6; Galatians 4:9-11 and Hebrews 4 to understand how the Sabbath was only a foreshadow of the Christ. We fulfill the Sabbath by trusting in Jesus.