Ummmm... might be a good idea to read the thread first before jumping in.... allready showed that your idea about Constantine is completely false.
As far as Scripture:
Matt. 28:1; Mark 16:2,9; John 20:1,19- t
he Gospel writers purposely reveal Jesus' resurrection and appearances were on Sunday. This is because Sunday had now become the most important day in the life of the Church.
Mark 13:5 And Jesus answering them began to say, Take heed lest any man deceive you: If ye love me, keep my commandments.John 14:15 I have kept my Father's commandmentsJohn 15:10 And it is easier for heaven and earth to pass, than one tittle of the law to fail. Luke 16:17
Acts 20:7 - this text shows the apostolic tradition of gathering together to celebrate the Eucharist on Sunday, the "first day of the week." Luke documents the principle worship was on Sunday because this was one of the departures from the Jewish form of worship.
And Paul, as his manner was, went in unto them, and three sabbath days reasoned with them out of the scriptures." Acts 17:2. "Paul and his company ... went into the synagogue on the sabbath day, and sat down." Acts 13:13, 14. "And on the sabbath we went out of the city by a river side, where prayer was wont to be made; and we sat down, and spake unto the women which resorted thither." Acts 16:13. "And he [Paul] reasoned in the synagogue every sabbath, and persuaded the Jews and the Greeks." Acts 18:4.
1 Cor. 16:2 - Paul instructs the Corinthians to make contributions to the churches "on the first day of the week," which is Sunday. This is because the primary day of Christian worship is Sunday.
Col. 2:16-17 - Paul teaches that the Sabbath was only a shadow of what was fulfilled in Christ, and says "let no one pass judgment any more over a Sabbath."
Romans 3:20 By the law is the knowledge of sin.
Romans 3:31 Do we then make void the law through faith? God forbid: yea, we establish the law
Romans 6:15 What then? Shall we sin (break God's law), because we are not under the law, but under grace? God Forbid
Romans 7:7 I had not known sin, but by the law: for I had not known lust, except the law had said, Thou shalt not covet.
Romans 8:3, 4 God sending his own Son ... condemned sin in the flesh: That the righteousness of the law might be fulfilled in us.
2 Thess. 2:15 - we are to hold fast to apostolic tradition, whether it is oral or written. The 2,000 year-old tradition of the Church is that the apostles changed the Sabbath day of worship from Saturday to Sunday.
Luke 16:17 And it is easier for heaven and earth to pass, than one tittle of the law to fail.
Psalms 89:34 My covenant will I not break, nor alter the thing that is gone out of my lips.
Psalms 111:7, 8 All his commandments are sure. They stand fast for ever and ever.
Malachi 3:6 For I am the Lord, I change not.
Heb. 4:8-9 - regarding the day of rest, if Joshua had given rest, God would not later speak of "another day," which is Sunday, the new Sabbath. Sunday is the first day of the week and the first day of the new creation brought about by our Lord's resurrection, which was on Sunday.
"All of us believe many things in regard to religion that we do not find in the Bible. For example, nowhere in the Bible do we find that Christ or the Apostles ordered that the Sabbath be changed from Saturday to Sunday. We have the commandment of God given to Moses to keep holy the Sabbath Day, that is the 7th day of the week, Saturday. Today most Christians keep Sunday because it has been revealed to us by the Church outside the Bible." The Catholic Virginian, "To Tell You The Truth, Vol. 22, No. 49 (Oct. 3, 1947).
Heb. 7:12 - when there is a change in the priesthood, there is a change in the law as well. Because we have a new Priest and a new sacrifice, we also have a new day of worship, which is Sunday.
"Protestants ... accept Sunday rather than Saturday as the day for public worship after the Catholic Church made the change... But the Protestant mind does not seem to realize that ... in observing Sunday, they are accepting the authority of the spokesman for the Church, the pope." Our Sunday Visitor, February 5th, 1950
Rev 1:10 - John specifically points out that he witnesses the heavenly Eucharistic liturgy on Sunday, the Lord's day, the new day of rest in Christ. Matt. 16:19; 18:18 - whatever the Church binds on earth is bound in heaven. Since the resurrection, Mass has been principally celebrated on Sunday.
''The [Roman Catholic] Church changed the observance of the Sabbath to Sunday by right of the divine, infallible authority given to her by her founder, Jesus Christ. The Protestant claiming the Bible to be the only guide of faith, has no warrant for observing Sunday. In this matter the Seventh-day Adventist is the only consistent Protestant.'' The Catholic Universe Bulletin, August 14, 1942, p. 4.
Hope that helps,
S