Why was the Sabbath changed to Sunday?

I have read a few different comments that the Catholic church changed the Sabbath day to Sunday because this is the day that the lord raised from the dead?

I also read that it was because of Sun Worship by non-catholics and the Roman Catholic church wanted to save these individuals?

What do I say to a Seventh Day Adventist that is asking these questions?

These links should be helpful in refuting Seventh-Day Adventists. CAF staff apologist Michelle Arnold grew up as an Adventist and has also written on the topic for Catholic Answers. If you have any further questions or concerns that are not answered by these links, please contact Catholic Answers directly.

Recommended Reading:
Why do Catholics worship on Sunday?
Who started the Seventh-Day Adventists?
How do I talk with a Seventh-Day Adventist?
Can you recommend resources on Seventh-Day Adventism?
Seventh-Day Adventism
Sabbath or Sunday?
From Sabbath to Sunday by James P. Guzek

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