The seven-day week adopted by the Romans did not come from the Jews. The astrologers invented it based on the fact that they knew of five planets plus the sun and the moon. Had they known of six planets, they would have had an eight-day week.
That's nonsense. It was instituted in the very first chapter of the very first book of God's Word, the Bible, in the Book of Genesis, at least 6000 years ago, way before anything called "Rome" was on the scene.