Originally Posted by brokenprism
"So then, there remains a Sabbath rest for the people of God..." NASB
"There remains, then, a Sabbath-rest for the people of God;" NIV
"There remains therefore a rest to the people of God." NKJV
And the literal Greek:
"Then remains a sabbath rest to the people of God." (Nestle)
NONE of those translations, 'averaged' from historic manuscripts, have the force of "It is the duty of the people of God to keep the Sabbath." That's just embarrassingly fabricated.
Heb 4:9 follows an argument about how the Jews could not enter God's rest, but that a 'Sabbath' rest was yet to come (the Sabbath law had been around quite a while -- why was this rest described as yet to come if it's the weekly Sabbath?) for those who put their trust in Christ and cease from their works. The Sabbath was a type, like everything else -- even the Sabbath God kept in Creation was about ceasing from His works.
What Fred is trying to do here is to blur the distinction between the law of Moses and the moral law of Ten Commandments to bolster his argument that the feast days are required to be kept by Christians.
Hebrews 4:9 is speaking of the faith and privilege it is for the people of God to rest on the day God designated as His Sabbath day. Rest is a blessing and a privilege not a work as Fred is trying to sell it. The context itself of Hebrews 4 is faith and as you noted, ceasing from works as God did.