Numbers 14:35
33 and your children will wander in the wilderness 40 years and suffer for your unfaithfulness, until your dead bodies lie finished in the wilderness. 34 According to the number of the days you have investigated this land, 40 days—one day for a year—you will suffer for your iniquities, 40 years, and you will know what it means to thwart me. 35 I, the Lord, have said, “I will surely do so to all this evil congregation that has gathered together against me. In this wilderness they will be finished, and there they will die!”’” 36 The men whom Moses sent to investigate the land, who returned and made the whole community murmur against him by producing an evil report about the land, 37 those men who produced the evil report about the land, died by the plague before the Lord.
Hebrews 3:17
15 As it says, “Oh, that today you would listen as he speaks! Do not harden your hearts as in the rebellion.” 16 For which ones heard and rebelled? Was it not all who came out of Egypt under Moses’ leadership? 17 And against whom was God provoked for forty years? Was it not those who sinned, whose dead bodies fell in the wilderness? 18 And to whom did he swear they would never enter into his rest, except those who were disobedient? 19 So we see that they could not enter because of unbelief.
Notes and References
"... There is, besides these two Scriptures, another Old Testament passage which figures in 3:7-4:11 although it is nowhere quoted. Psalm 95 (LXX 94) recalls the events recorded in Exodus 17:1-7 and Numbers 20:1-13, yet, as Hofius has demonstrated at length, the author has, like some of the rabbis, understood this psalm primarily against the backdrop of Numbers 14. A careful study of the events at Kadesh in LXX Numbers 14 as well as the remainder of the Old Testament bring to light a number of recurring and prominent features, several of which are plainly present in Hebrews 3-4 ... In addition to the specific parallels mentioned by Hofius, Laansma adds that the reference to those in Hebrews 3:17 is derived from Numbers 14:32... this makes the case very strong that Auctor composed this entire passage (Hebrews 3, 7-4, 11) with Numbers 14 open before him ..."
Gallos, Erhard Katapausis and Sabbatismos in Hebrews 4 (pp. 161-162) Andrews University, 2011