6 Since therefore it remains that some must enter it, and those to whom it was first preached did not enter because of disobedience,
7 again He designates a certain day, saying in David, “Today,” after such a long time, as it has been said: “Today, if you will hear His voice, do not harden your hearts.”
8 For if Joshua had given them rest, then He would not afterward have spoken of another day.
9 There remains therefore a rest for the people of God.
10 For he who has entered His rest has himself also ceased from his works as God did from His.
11 Let us therefore be diligent to enter that rest, lest anyone fall according to the same example of disobedience.
it remains (v.6) = remains over from past times — God’s promises can’t be voided by man’s action — some will enter rest
Verse 5 makes it clear that those who did not believe will not enter God’s rest. Therefore (v.6), there must be a rest and some must enter into it.
Those to whom rest was first preached — the Israelites of Moses’ day (v.6) — didn’t believe and, therefore, didn’t enter into rest (Canaan).
Even under David (v.7), God was still promising a future day of rest for those who believe.
The quote in verse 7 is from Psalm 95.
such a long time (v.7) — from Moses to David — five centuries — 500 years later God makes another offer of rest.
as it has been said (v.7) — said before and still on the record
Under Moses, the rest was not accepted. Under Joshua, the rest was not final.
Even under Joshua, after he finally led the people into Canaan, God was still talking of a future day of rest (v.8), so Canaan wasn’t the ultimate rest.
The “therefore” (v.9) is, first of all, a general inference drawn from all that precedes. A “promise is left” of entering into God’s rest (v.1). That promise must be appropriated, “mixed with faith” in those who hear it (v.2). Only believers will enter that rest, for God has sworn that unblievers shall not enter therein (v.3). Although there is a rest of God mentioned in Genesis 2 (vs. 2-3), and although Joshua led Israel into the rest of Canaan (v.8), yet neither of these “rests” was what is promised [believers] (v.8). Hence, we can only conclude there is another “rest” for God’s people (v.9). — An Exposition of Hebrews, by Arthur W. Pink, page 128.
The writer uses here (v.9) a different Greek word for “rest.” In his previous references to the idea of rest, he has used katapausis, meaning “a cessation from activity,” thus “a rest,” a general word for the idea of rest. Now, he uses sabbatismos, the word used of the Sabbath rest. The word points back to God’s original rest, and speaks of the ideal rest. It is a Sabbath rest because the believer reaches a definite stage of attainment and has satisfactorily accomplished a purpose, as God did when He finished the work of creation. It is not the believer’s rest into which he enters and in which he participates, but in God’s unique, personal rest in which the believer shares. — Hebrews in the Greek New Testament, by Kenneth S. Wuest, page 87.
be diligent (v.11) = make haste — The Jews were being warned not to miss out on rest because of unbelief as those in Moses’ day did.
The ultimate rest in Christ (v.11) is still future. Jesus is better than Joshua because He provides a better rest. Joshua’s rest was temporal, physical and material. Christ’s rest is spiritual and eternal.