"But this man, after he had offered one sacrifice for sins for ever, sat down on the right hand of God;" (Hebrews 10: 12)
When Jesus sat down, he put away our sins.
For how long? Forever.
"And the work of righteousness shall be peace; and the effect of righteousness quietness and assurance for ever." "(Isaiah 32: 17)
God the Father establishes us in this righteousness":
"In righteousness shalt thou be established: thou shalt be far from oppression; for thou shalt not fear: and from terror; for it shall not come near thee." (Isaiah 54: 14)
Daniel received the prophesy of this everlasting righteousness:
"Seventy weeks are determined upon thy people and upon thy holy city, to finish the transgression, and to make an end of sins, and to make reconciliation for iniquity, and to bring in everlasting righteousness, and to seal up the vision and prophecy, and to anoint the most Holy." (Daniel 9: 24)
and of course:
"For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life." (John 3: 16)
This righteousness is a gift which we keep on receiving:
"For if by one man's offence death reigned by one; much more they which receive abundance of grace and of the gift of righteousness shall reign in life by one, Jesus Christ." (Romans 5: 17)
This is a gift we can keep on receiving:
"As it is written, He hath dispersed abroad; he hath given to the poor: his righteousness remaineth for ever." (2 Corinthians 9: 9)
When Jesus sat down, His Father then promised to make every one of His enemies His footstool:
"But to which of the angels said he at any time, Sit on my right hand, until I make thine enemies thy footstool?" (Hebrews 1: 3)
We are established in His righteousness, a gift which we keep on receiving, and God invites us to rest and receive all things from Him because of this gift of righteousness.
Jesus has sat down, and He has finished the work. When will you?