In Hebrews four we find that the children of Israel were not able to enter into God’s rest which was the promised land because of their lack of faith.
And Hebrews three tells us what their lack of faith was. It is Sin, any sin is showing unbelief, lack of faith.
They refused God's Spirit and the Life He offers through it,. Which is the true promised land and the Gospel that verse 4:2 brings out that we who have believe partake of. (see verse 3}
Heb 3:17 But with whom was he grieved forty years? was it not with them that had sinned, whose carcases fell in the wilderness?
Heb 3:18 And to whom sware he that they should not enter into his rest, but to them that believed not?
Heb 3:19 So we see that they could not enter in because of unbelief.
And God’s rest that remains for us today, the Sabbath rest, is to enter into eternal bliss with Jesus Christ and our father.
Two rests mentioned in Hebrews four not one. The rest which is the Gospel, and the rest God took on the seventh day.
They are not the same.
We who believe do enter into the rest which is the Gospel. This is seen in verse 2 and 3.
Verse 4 says He, God spake in a certain place of the seventh day on this wise, And God did rest from all His works.
This was spoken as commandment.
Verse 5 say in this again. In this again what?
In this again He speaks of the seventh day if we enter into His rest which is the Gospel.
Verse 9 and 10 speaks in reference to verse 5. Verse 10 says the same thing but in different words. And by the use of the word also makes a clear cut distinction between the Gospel rest in which we have entered and the rest that God did when He rested from all His works. The text states that we who Have entered into his rest which is the Gospel mentioned previously ALSO cease from our own works AS God did from His. God did not enter into the Gospel rest. He ceased His work on the Seventh Day. So, we AS He cease from our own work as He did on the Seventh Day
Heb 4:2 For unto us was the gospel preached, as well as unto them: but the word preached did not profit them, not being mixed with faith in them that heard it.
Heb 4:3 For we which have believed do enter into rest, as he said, As I have sworn in my wrath, if they shall enter into my rest: although the works were finished from the foundation of the world.
Heb 4:4 For he spake in a certain place of the seventh day on this wise, And God did rest the seventh day from all his works.
Heb 4:5 And in this again, If they shall enter into my rest.
Heb 4:9 there remains, then, a Sabbath rest to the people of God,
Heb 4:10 for he who entered into his rest, he also rested from his works, as God from His own.