Dr. Jack L. Arnold



Lesson 10

The Warning Against Unbelief

Hebrews 3:6-12


What do you think is the greatest sin a person can commit?  Is it murder, adultery, homosexuality, lying or stealing?  According to the book of Hebrews, the greatest sin of man is unbelief, for all sins stem from man’s sin of unbelief.  Unbelief is the worst sin, for without belief in the living God a person cannot be saved.


One of the major reasons for the book of Hebrews is to challenge Christians to examine the reality of their commitment to Christ.  Is it genuine or false?  Is it real or superficial?  The warnings in this book are designed to cause the professing Christian to look inward to see if there is true saving faith in Christ.




This section will not make much sense unless we clearly understand why this book was written.  The recipients of this letter were professing Hebrew-Christians who had come out of Judaism to serve Christ as Christians.  They were undergoing much social persecution from the unbelieving Jews and were beginning to doubt the reality of Christ.  Some of them had already left the Christian assembly to go back into Judaism, and others were seriously contemplating this move.


The author of Hebrews, therefore, pleads with them not to go back into Judaism and warns them of the devastating consequences of this move.  If they go back into Judaism, they turn from Christ and declare themselves to be, by life and lip, unbelievers.  The author is very concerned that there might be some unbelievers in this group of professing Hebrew-Christians.  Therefore, he writes to warn them of the terrible consequences if they leave Christ.


The emphasis in this whole epistle is upon man’s responsibility to respond positively to the truth of Christ, and if they do not respond this is good evidence that they are not truly born of God’s Spirit.




“...whose house are we, if we hold fast our confidence and the boast of the hope firm unto the end.” -- The author has been telling us why Christ is superior to Moses by comparing their ministries and the people they ministered to.  Moses was a servant in the temporal house of Israel.  Christ is the ruler over His spiritual house, the Church.  The author then makes the statement that we are the house of Christ, the Church, “if” we hold fast to the Faith up to the end of our lives.


This does not teach that a person can be saved and then lost but that a person who is truly saved will push on in the Faith, giving evidence of real spiritual life.




“Therefore…” -- The author has been speaking about Moses and Christ and his mind apparently flashed back to an incident in the Old Testament that illustrates how a certain group of people failed to persevere in the Faith and were judged by God.  The author goes back to that first generation of Jews that came out of Egypt under Moses’ leadership.  This group of Hebrews, as a whole, failed to persevere because they did not have true saving faith.  They were not permitted to enter into the Promised Land because of their continued unbelief.


The rest in Canaan in this context is a picture or type of salvation.  The basic premise of the argument is: Faith was necessary for entrance into temporal Canaan and it is also necessary for entrance into heaven, our spiritual Canaan.


“Therefore, just as the Holy Spirit says...” -- The author now goes to Psalm 95:7-11 to show from the Old Testament that people who profess Christ and do not persevere were never saved in the first place.


The author of Hebrews recognized Psalm 95 to be inspired by the Holy Spirit, even though King David was the human writer of this Psalm.


“‘TODAY IF YOU HEAR HIS VOICE’” -- This “today” is timeless for it applied to the children of Israel, to King David, to the professing Hebrew-Christians to whom this letter was written, and this also applies to us today.  “Today” looks at the time of grace that a person has to trust before the end of opportunity to believe comes at death.  The opportunity for salvation is now, today. “...behold, now is ‘THE ACCEPTABLE TIME,’ NOW IS ‘THE DAY OF SALVATION’”  (2 Cor. 6:2b). There is no assurance that there will be a tomorrow!


Notice carefully the conditional “if.”  “If” they will hear the voice of God and the option is there that they may willfully choose not to hear the voice of God.  It becomes a matter of a submissive will to a sovereign God.


“‘DO NOT HARDEN YOUR HEARTS’...” -- These Hebrew-Christians were not to harden their hearts as did the children of Israel in the Old Testament.  They were in the process of hardening, for this literally says, “Stop hardening your hearts!”  Each contemplation of leaving Christ to go back into Judaism was a further hardening of their hearts.


It is quite possible for men to harden their hearts to the person of God.  Men do not hear the voice of God because they continue to harden their hearts to Him and His truth as revealed in Holy Scripture.


Note very carefully that a man hardens his heart, which is the seat of our moral being, namely our emotions.  It is not the head that is called into dispute but a man’s love for God and the truth of God.  The children of Israel had head knowledge about God.  They knew He was sovereign, loving, holy and good but they refused to bow themselves to this God and do His will.


“…‘AS WHEN THEY PROVOKED ME, AS IN THE DAY OF TRIAL IN THE WILDERNESS, WHERE YOUR FATHERS TRIED ME BY TESTING ME, AND SAW MY WORKS FOR FORTY YEARS.” -- The “day of trial” does not refer to one particular day in Israel’s history but to the whole forty years of its wandering in the wilderness.  The Israelites had absolutely no reason to test God, for they experienced the mercies and miracles of God for forty years.  They had seen great miracles in Egypt; they saw God open the Red Sea; they saw God destroy Pharaoh and his mighty armies.  God provided in a miraculous way food, water and clothing for the Israelites.  Jehovah was with them in the cloud by day and the pillar of fire by night.  The journey from Egypt to Canaan should have taken no more than two weeks but it took forty years because they were a stiff-necked and rebellious people who refused to submit to God even though His works were all about them.


The first year of the forty years at Rephidim we find the children of Israel griping and complaining against Moses and God because there was no water (Exodus 17:1-7).  Forty years later at Kadesh we find the same generation complaining and griping about no water (Num. 20:1-13).  During their whole time in the wilderness, they learned nothing about trusting God.  The Israelites who came out of Egypt were characterized by unbelief, and this unbelief was manifested by a complaining spirit, by an attack on Moses their leader and by rebellion to God.  Forty years of wandering did not change their unbelieving hearts.


How did they test God?  They tested Him by failing to believe His promise to take them to Canaan.  They tested Him by rebelling against His sovereignty.  They tested God by failing to believe in His ability to meet their needs, for they said, “Is the Lord among us, or not” (Exodus 17:7)?  They tested God by negatively believing that God would not bring judgment down upon them if they did not obey Him.  They said, “God is a God of love; He won’t judge us!”


“‘THEREFORE I WAS ANGRY WITH THIS GENERATION, AND SAID, ‘THEY ALWAYS GO ASTRAY IN THEIR HEART; AND THEY DID NOT KNOW MY WAYS’” --  God said He was “grieved” with that generation but the word is much stronger; it means to be “angry, disgusted or vomit out.”  These Israelites “always” went astray and they did not know God’s ways.  They were perpetual unbelievers, and while they knew of God’s acts, they did not know of His ways, for they would not yield themselves to God.  Their lives did not give evidence of true saving faith in the living God.


True believers can have lapses in faith but they cannot always go astray and never know His ways.  A true believer will want to know God’s ways.  “Teach me Thy way, O Lord...” (Psalm 27:11)


“‘AS I SWORE IN MY WRATH, THEY SHALL NOT ENTER MY REST.’”  -- God refused to take the Israelites into the Promised Land because of their unbelief.  The “rest” is Canaan but Canaan is typical of heaven’s rest for the true believer.  God made an oath, sealed in His anger, that they would not enter into His promised rest.


Not every person who came out of Egypt was an unbeliever. Some, however, were unbelievers and it is to these that the author is speaking because he wants to challenge the profession of the Hebrew-Christians.  We know that the whole generation of Israelites experienced the judgment of God.  Some who came out of Egypt but did not enter the land were true believers who were more rebellious than submissive to God, but they died in divine discipline before they ever entered into the Promised Land.  Their rebellion brought them physical death, we know that this was true of Moses and Aaron (Num. 20:12).  These two were saved but never went into the land, so we might conclude that there were others as well.


“Now I desire to remind you, though you know all things once for all, that the Lord, after saving a people out of the land of Egypt, subsequently destroyed those who did not believe.  And angels who did not keep their own domain, but abandoned their proper abode.  He has kept in eternal bonds under darkness for the judgment of the great day. Just as Sodom and Gomorrah, and the cities around them, since they in the same way as these indulged in gross immorality and went after strange flesh are exhibited as an example, in undergoing the punishment of eternal fire” (Jude 5-7).


However, some and probably the great majority of the Israelites who came out of Egypt were not saved because they had unbelieving hearts that were hardened to God.  It is primarily to this group of professing believers in the wilderness that the author of Hebrews is referring.  They were within the professing, chosen people of God but they were not saved.  They were outwardly religious but were rebels to God.  They professed faith in God but showed only unbelief in their actions.  They had knowledge of God but their hearts were hardened to Him.


Whether mere professors of God or weak believers in God, the two million people that left Egypt died in the wilderness because of unbelief.  The only exceptions were Joshua and Caleb who believed God and said in great faith that Israel could defeat the Canaanites and take the land (Num. 26:45,65).  The judgment of God is sure and stern upon all rebels to the living God.


God’s anger burned hot against that generation of Israelites.  His judgment fell upon them because they refused to believe God and obey Him.  They were rebels and God destroyed them.


THE WARNING (Heb. 3:12)


“Take care, brethren…” -- Literally this says, “Watch out, brethren,” for some of these professing Hebrew-Christians were on the verge of leaving Christianity to go back into Judaism.  The writer assumes his readers are genuine in their profession, but he does not want there to be the slightest possibility of error.  While assuming the reality of their conversion, he cannot take it for granted.  He, therefore, sounds the alarm: “Look out, brethren!  You may be guilty of a mere profession of faith as many Israelites of old were only professors.  Their unbelief caused them not to enter God’s rest of salvation.”


“...lest there should be in any one of you an evil, unbelieving heart, in falling away (apostatizing) from the living God.” -- A person who has once professed Christ and goes back into false religion or paganism is guilty of apostasy.  An apostate is one who intellectually knows the truth, but turns from it and goes away from Christ.  An apostate is a professor and not a possessor of Christ.


Any professing Christian can become an apostate when he turns from Christ but a possessing Christian can never become apostate.




Have you entered into God’s heavenly rest? You may be a person who has been a church member and sympathetic with Christianity and still not be saved because you have never really believed.  You may be a person who has seen God’s acts but do not know His ways.  It is possible to know all the facts about Christ and not know Him in your experience.  If this is your case, you are in great danger.


Remember, all who left Egypt did not enter into Canaan, and all who profess Christ do not enter into the heavenly rest.  Men may hear about Christ and not believe in Him.  Men may intellectually comprehend the supernatural workings of God and yet never submit to Him.  The common grace of God in the gospel may come to a person, but come in vain because it meets unbelief.


What is it that keeps you from the spiritual rest of heaven? It is your unbelief and disobedience of Christ. You cannot enter into rest because of your unbelief. “Come to Me, all who are weary and heavy laden, and I will give you rest.” (Matt. 11:28).