"And [God] hath raised us up together, and made us sit together in heavenly places in Christ Jesus:"
Many new teachings emphasize that we must learn to rest, to learn who we are in Christ and "sit down."
I spent a lot of time trying to sit down, therefore. Whenever I felt out of place, or thought wrong, I would recite "I am the righteousness of Christ" in or to "get seated" once again.
One of the verses which substantiated this habit is found in Hebrews 4:
"Let us labour
therefore to enter into that rest, lest any man fall after the same example of
unbelief." (Hebrews 4: 11)
"Labor" is one translation, perhaps inexact of "Σπουδάσωμεν which means "be diligent, or earnest" to enter.
This rest is based on belief, and we are called to believe on One Person:
"29Jesus answered and said
unto them, This is the work of God, that ye believe on him whom he hath sent." (John 6: 29)
Paul expressed the culmination of this call:
"I am crucified with Christ: nevertheless I live; yet not I, but Christ liveth in
me: and the life which I now live in the flesh I live by the faith of the Son of
God, who loved me, and gave himself for me. I do not frustrate
the grace of God: for if righteousness come by the law, then Christ is
dead in vain." (Galatians 2: 20-21)
Jesus Christ now lives in every believer (Colossians 1: 27), and we live by His faith within us.
In effect, because of who we are in Christ, we are already seated, already at rest in Christ.
It is no longer a matter of learning to "sit", but rather renewing our minds to the truth (Romans 12: 2) of who we are in Christ. As for Hebrews 4:11, that passage, like all the other in the Book of Hebrews, was written to the Hebrews, specifically those Jews who knew that Jesus was the Messiah, yet refused to believe that He is the final sacrifice for their sins.
If you are still wondering what you "must do", Romans 5: 17 provides the answer:
"For if by one man's
offence death reigned by one; much more they which receive [lit. are receiving] abundance of grace
and of the gift of righteousness shall reign in life by one, Jesus Christ." (Romans 5: 17)
Peter also offered the "one thing" needed:
"But grow in grace,
and in the knowledge of our Lord and Saviour Jesus Christ. To him
be glory both now and for ever. Amen." (2 Peter 3: 18)
Stop trying to sit down, stop trying to rest. In Christ, you are at rest.