The Peril of Unbelief

12 Take care, brethren, that there not be in any one of you an evil, unbelieving heart that falls away from the living God. 13 But encourage one another day after day, as long as it is still called “Today,” so that none of you will be hardened by the deceitfulness of sin. 14 For we have become partakers of Christ, if we hold fast the beginning of our assurance firm until the end, 15 while it is said,

“Today if you hear His voice, Do not harden your hearts, as when they provoked Me.” 16 For who provoked Him when they had heard? Indeed, did not all those who came out of Egypt led by Moses? 17 And with whom was He angry for forty years? Was it not with those who sinned, whose bodies fell in the wilderness? 18 And to whom did He swear that they would not enter His rest, but to those who were disobedient? 19 So we see that they were not able to enter because of unbelief.

(Hebrews 3:12-19)