1 Chronicles 17:27
Now therefore let it please thee to bless the house of thy servant, that it may be before thee for ever: for thou blessest, O LORD, and it shall be blessed for ever. Now therefore let it please thee to bless the house of thy servant, that it may be before thee for ever: for thou blessest, O LORD, and it shall be blessed for ever.
The verse belongs to the account of David's plans concerning the house of God, when he first conceived the design of building a house worthy of the divine majesty and opened his mind to the prophet Nathan about it. God accepted David's good intentions yet refused him the honor of building the temple. In that setting the verse records David's prayer and appeal that God would be pleased to bless his house, household and servant, that it might endure and remain before Him forever. The blessing God gives is what makes the servant's household endure before Him, so the prayer rests on the confidence that what the Lord blesses is secure forever because He blesses it.
What God blesses remains blessed forever, and what He blesses is lasting and secure forever because the Lord blesses it. God's blessing rests on His servant and remains forever, making the house blessed and enduring before Him. Applied to creation, this means the blessing God placed on the seventh day at the close of creation week, when He blessed and sanctified it, has never been removed or taken from it. The seventh day is therefore still His blessed, sanctified rest day, set apart for man's holy use for all time.
That permanence means God's blessing of the Sabbath extends to every succeeding seventh day and cannot be removed or transferred to another day. The seventh day has been blessed from the beginning and will remain blessed forever. God has never sanctified another day as the weekly Sabbath, for the blessing put on the seventh day at the close of creation week abides upon it still.