sojourner,
re: "I suppose you didn’t know that the first Christians went to synagogue on Saturday, because they were observant Jews. then, they also celebrated the Resurrection on the first day of the week (according to the Bible, the day of the Resurrection)."
Actually, scripture is silent with regard to anyone celebrating the resurrection on the first day of the week.
re: "There is scripture that alludes to Sunday as the Lord’s day."
I'm not aware of any scripture which does that. What do you have in mind?
re: "I suppose you didn’t know that the first Christians went to synagogue on Saturday, because they were observant Jews. then, they also celebrated the Resurrection on the first day of the week (according to the Bible, the day of the Resurrection)."
Actually, scripture is silent with regard to anyone celebrating the resurrection on the first day of the week.
re: "There is scripture that alludes to Sunday as the Lord’s day."
I'm not aware of any scripture which does that. What do you have in mind?