ichuka:
To whom was God speaking when He took an oath that they would never enter His rest? Wasn’t it the people who disobeyed Him? (Hebrews 3:18 NLT)

We have no right to go to the unsaved and bid them come to Christ and find rest until and unless we ourselves know that rest. Our testimony and our ministry is jeopardized, weakened, limited and discredited if we are not ourselves in rest; and this is the object of the enemy's activity in this matter – to discredit us by taking from us that very birthright of our union with Him Who is never perturbed, never anxious, never in doubt as to the issue, the One Who reigns. You see, rest is the practical outworking of our belief that He is Lord, and the very Lordship of Christ is struck at by the unrest of the people of God....

Do not think that it is necessarily such-and-such things that account for our condition. These may be contributing factors, they may be very testing, may bear upon us very heavily. Physical matters – yes, they do press, they do make the situation exceedingly difficult, they do make a difference. Circumstances in which we have to live our lives, they do make a lot of difference, they make the situation exceedingly difficult. We say, "If only the Lord would deal with this physical matter or these circumstances or this something else! It is all due to that, that is the cause of it, the reason for it." That is our way of reasoning, but it is not the Lord's thought at all. The thing is deeper down than that, and it is simply a matter of believing God; resolute faith, confidence in God. The Lord is trying to get us out of our variable and varying soul life where we are at the mercy of all our feelings, thoughts and reasonings and all that kind of thing, into a realm where, in spirit, we are steadfast. That is the point upon which it is all fixed in the Psalm. "Their heart was not steadfast with Him" (Psa. 78:37), and around that the whole of their forty years is gathered. The key to this is spiritual; tested by every other line, every other means, it is a spiritual matter ultimately. To be strengthened with might by His Spirit in the inward man (Eph. 3:16) is the answer to it all.

ichuka:
Heb 4:10 New Living Translation
"For all who have entered into God’s rest have rested from their labors, just as God did after creating the world."

ichuka:
Let us then be eager to know this rest for ourselves, and let us beware that no one misses it through falling into the same kind of unbelief as those we have mentioned. (Hebrews 4:11 Phillips)

Those who failed to go in failed, it says, to enter into His rest. Those to whom the Gospel was afore preached failed to enter in. That is remarkable! The Gospel was preached to them. These are they to whom the Gospel was afore preached. What is the Gospel? To answer the inquiry in that connection, it is Christ as our Rest. That is the Gospel: and the Gospel of Christ as our Rest was preached to them in type, and they to whom the Gospel was afore preached failed to enter in. Then, says the Apostle, "Let us therefore give diligence to enter into that rest, that no man fall after the same example of disobedience." They failed! God set forth another day, saying, "Today if ye shall hear His voice, harden not your hearts...." The Gospel is preached to believers to enter into His Rest. The Lord Jesus put this in the germ form of truth when He said: "Come unto Me, all ye that labor and are heavy laden, and I will give you rest. Take My yoke upon you, and learn of Me; for I am meek and lowly in heart; and ye shall find rest unto your souls." Christ in heaven is our spiritual Rest, heart rest.

What is the essence of rest? It is satisfaction and assurance. If you are satisfied, you are at rest, no matter how much work you have to do. And if you are quite sure that your work is going to be successful, you have assurance, and you are in rest. Everything for us is based upon Christ having entered as the Forerunner, and having become our Rest. We shall labor: we shall pour ourselves out; we shall spend; we shall be spent; but in it all there can be real heart rest. We shall be assailed: we shall be pressed on every side; we shall be cast down; we shall be tried; but Christ can still remain our Rest: for in the first place, we know that these things are not going to be to our destruction, since He has destroyed the power of destruction; and, in the second place, that our labors are not in vain, because He has swallowed up death victoriously. He is our Rest.