Hebrews 3:18-4:2

King James Version

¹⁸ And to whom sware he that they should not enter into his rest, but to them that believed not?

¹⁹ So we see that they could not enter in because of unbelief.

4 Let us therefore fear, lest, a promise being left us of entering into his rest, any of you should seem to come short of it.

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.