Unbelief makes us wanderers in this wilderness

Numbers 32:13-15 (ESV)
And the LORD's anger was kindled against Israel, and he made them wander in the wilderness forty years, until all the generation that had done evil in the sight of the LORD was gone. [14] And behold, you have risen in your fathers' place, a brood of sinful men, to increase still more the fierce anger of the LORD against Israel! [15] For if you turn away from following him, he will again abandon them in the wilderness, and you will destroy all this people."

He made them wander in the wilderness. God's wrath makes us to wander in confusion. A meaningless life is the judgment of God's wrath. How close did this first generation come to the promised land, yet fell short, for they believed not. The unbelievers also live lives that are so close to the Kingdom of God, but yet are so far from it, because they believe not God. It is a futile life. Hear what Christ said:
Mark 12:32-34 (ESV)
And the scribe said to him, "You are right, Teacher. You have truly said that he is one, and there is no other besides him. [33] And to love him with all the heart and with all the understanding and with all the strength, and to love one's neighbor as oneself, is much more than all whole burnt offerings and sacrifices." [34] And when Jesus saw that he answered wisely, he said to him, "You are not far from the kingdom of God." And after that no one dared to ask him any more questions.
The scribe was so close to the kingdom of God for he knew what the law was about. But though he was so close, but he was so far from it because he did not realize that it was by faith in Christ that one enters into the Kingdom. He did not realize that the law was not to keep, but to show how much he needed a Saviour. Therefore Christ says, though he is not far, he has not yet arrived. He now needed to forsake all hope in self, and trust in Jesus Christ. No one knows if the scribe went on to believe in Christ, but if not, then it was a tragic and meaningless life indeed, spent so close to the gates of heaven yet never entering in. It is therefore the most fearful thing to be cursed with unbelief, as the first generation was. Let us always pray that God grant us soft hearts, lest our hearts be calloused beyond repair, unable to believe in God any longer.

The first generation wandered in the wilderness for forty years until all perished. Such also is the mortification that God will work within a believer. God will make us to wander in self-righteousness and law-keeping, until we completely become undone, and desire nothing but death to self. God always wants to recognize this: that we CAN'T do it. How much failures do we need to go through until we realize that there is no good thing within us, and that it is all by God's grace. How many times must we be surprised at our sins until we realize that we are wicked, and that it is by Jesus Christ's righteousness that we are accepted. God will make us to wander, forty years if it have to be, until we realize that we ought to trust in Christ alone. And thank God that He does this work in us, until the old man that wants self glory be destroyed from within us. God will form in us a new man after the image of Christ, a new man that wholly believes in God's mercy and power. The wilderness is not an aimless wandering for us, then. Just as Joshua and Caleb wandered with the generation that died, though we wander, it shall be for our good, and not for our harm. It shall be for the building of our character, and it shall be a journey and a walk with Christ, renewing us day by day.

Did not Christ also wander in the wilderness for our sins? He went through 40 days in the desert, being tempted, that God may prove what was in His heart. Unlike Israel, there was nothing found in Christ but sincere devotion to the Law of God. Also, as our Scapegoat, Christ, carrying all our sins, was cast out from the gate as to wander in the wilderness until He perished by the hands of Gentiles:
Leviticus 16:21-22 (KJV)
And Aaron shall lay both his hands upon the head of the live goat, and confess over him all the iniquities of the children of Israel, and all their transgressions in all their sins, putting them upon the head of the goat, and shall send him away by the hand of a fit man into the wilderness: [22] And the goat shall bear upon him all their iniquities unto a land not inhabited: and he shall let go the goat in the wilderness.
Christ was treated as a man who believed none of God's promises. He was treated like the first generation that went out of Egypt, and was released into the wilderness of God's wrath until He was consumed. Christ died for our unbelief. Christ was consumed for our hardened hearts that rebelled against God and His ways. Christ died for our doubting of His word. Christ died for our belief in ourselves. Christ died for us trusting in our own strength, all our attempts to establish our own righteousness. Because Christ died for our unbelief, God can allow His children to go in to His Kingdom though there are moments where His children do not believe. Because Christ died, God can be faithful to us though sometimes we are faithless. It is therefore not up to our own faith alone that we are saved, but because of God's grace. Christ died for the imperfect faith of His people. He perished in the wilderness like an unbeliever ought to be perished. Therefore He can have mercy on His elect who sometimes believe not. We thank God then, that our salvation is not up to our faith alone, but up to Jesus Christ. Praise be to God our Saviour.

You have risen in your fathers' place, a brood of sinful men. Moses gives their fathers no respect, calling them 'a brood of sinful men'. Moses is commanding them to disassociate all ties with the sinful actions of their fathers. Sometimes we ought to view our fathers as who they are, as sinners. Too much respect of our fathers is nothing but idolatry. God the Father of our Lord Jesus Christ has become our Father, as it is written:
Matthew 23:9 (KJV)
And call no man your father upon the earth: for one is your Father, which is in heaven.
Jesus also was called the son of Mary and Joseph according to the flesh, but He showed no more respect than He ought to have, for His Father was in heaven:
Luke 2:49 (KJV)
And he said unto them, How is it that ye sought me? wist ye not that I must be about my Father's business?
Let us have like attitude, and give not honour to men than is commanded. We ought to take the place of our Father in heaven, and do the things that He does, being Holy as He is holy. Our parents all have mistakes, and in the light to God's holy law, in all honesty they can be called nothing but a brood of sinful men. Let us not exalt our earthly fathers more than required, lest we imitate their sin and offend God as they did.

To increase still the more the fierce anger of the Lord. God was already angry with Israel because of the wickedness that their fathers had committed. God has several times desired to destroy them all because of their sins, only to show then mercy by the intercession of Moses. Indeed God's wrath is being stored and increasing against those who believe not in the Gospel. God is slow to anger, but this does not mean that His anger will be decreased. It is increasing. And if we have been delaying and adding to God's wrath ever since the fall of Adam, what will be the revelation of His anger and fury on the Day of wrath? There shall be no escape. God's wrath is like rain waters being stored in the dam of His patience. He shall not be patient towards sinners forever, but as they fill up the measure of their offense, so shall the righteous anger of God increase until on Judgment Day it shall be released in full upon the kingdoms of men to destroy them. Some evidences of this truth in scripture:
Genesis 15:16 (KJV)
But in the fourth generation they shall come hither again: for the iniquity of the Amorites is not yet full.
Revelation 18:4-5 (KJV)
And I heard another voice from heaven, saying, Come out of her, my people, that ye be not partakers of her sins, and that ye receive not of her plagues. [5] For her sins have reached unto heaven, and God hath remembered her iniquities.
Genesis 6:13 (KJV)
And God said unto Noah, The end of all flesh is come before me; for the earth is filled with violence through them; and, behold, I will destroy them with the earth.
Only those who have trusted Christ as the satisfaction for God's wrath shall escape this coming flood of God's wrath that is to come upon the earth.

Also, those who have received the grace of having this wrath removed must not continue in sin. This second generation had been saved from destruction by Moses' intercession. God's wrath was to wipe them all away with their fathers, but Moses, who is a type of Christ, asked for mercy:
Numbers 14:15-20 (ESV)
Now if you kill this people as one man, then the nations who have heard your fame will say, [16] ''It is because the LORD was not able to bring this people into the land that he swore to give to them that he has killed them in the wilderness.'' [17] And now, please let the power of the Lord be great as you have promised, saying, [18] ''The LORD is slow to anger and abounding in steadfast love, forgiving iniquity and transgression, but he will by no means clear the guilty, visiting the iniquity of the fathers on the children, to the third and the fourth generation.'' [19] Please pardon the iniquity of this people, according to the greatness of your steadfast love, just as you have forgiven this people, from Egypt until now." [20] Then the LORD said, "I have pardoned, according to your word.
Likewise, we believers have been spared from eternal punishment by the everlasting mercy of God that came forth from the death of His Son. It was Christ who convinced His own Father to turn away His wrath because of His own shed blood. It is Christ Himself who died, as though in the wilderness, bearing our guilt and wrath that was due upon us. But having received this grace, are to commit the same sins that we have committed before? By no means. As it is written in Hebrews:
Hebrews 10:28-31 (ESV)
Anyone who has set aside the law of Moses dies without mercy on the evidence of two or three witnesses. [29] How much worse punishment, do you think, will be deserved by the one who has spurned the Son of God, and has profaned the blood of the covenant by which he was sanctified, and has outraged the Spirit of grace? [30] For we know him who said, "Vengeance is mine; I will repay." And again, "The Lord will judge his people." [31] It is a fearful thing to fall into the hands of the living God.
It is not possible that those who have received mercy continue in sin, for in doing so we crucify our Lord afresh, spurn the Son of God and profane His blood and grieve His Spirit. Could the second generation expect to be saved while committing the same sins for which the first generation died? By no means. Likewise we cannot expect to be saved while continuing in the sins that crucified our Lord. Let us cherish the grace by which our Lord suffered for our sins, and pursue holiness.

If you turn away from following Him, He will again abandon them in the wilderness. God abandons those who choose not to follow Him in faith. The reason we wander aimlessly is because we have not chosen to follow Christ, and thus our Guide has abandoned us. He will not come back to chase those who have forsaken the Lord. We must been drawn to Him first. Hear James:
James 4:8 (ESV)
Draw near to God, and he will draw near to you. Cleanse your hands, you sinners, and purify your hearts, you double-minded.
But this drawing is not the result of our works, but by God's grace:
John 6:44 (ESV)
No one can come to me unless the Father who sent me draws him. And I will raise him up on the last day.
We who have received this grace, then, must go to Him, and follow Him closely, lest we be abandoned by Lord in this wilderness. He is our eyes in this life, but if we turn away from Him, and He abandon us, how shall we ever see the path that leads to life? Christ said, 'Come to Me all you who thirst' and 'Come to Me all who are burdened'. But if we obey not His command and draw not near to Him, how shall we quench our thirst and be eased of our burdens? Christ will not walk together with those who trust not in Him, but will abandon them like orphans. Indeed, God cannot work with unbelief:
Hebrews 11:6 (ESV)
And without faith it is impossible to please him, for whoever would draw near to God must believe that he exists and that he rewards those who seek him.
And,
Romans 8:7-8 (ESV)
For the mind that is set on the flesh is hostile to God, for it does not submit to God's law; indeed, it cannot. [8] Those who are in the flesh cannot please God.
This mind therefore that is set on the flesh is mind that believes not. The unbelieving mind therefore is the mind that does not and cannot submit to God's law. The first generation that came out of Egypt followed not God because they believed Him not. Because they believed Him not, they could not and would not submit to His law. And because they submitted not, God was not pleased to walk with them, and abandoned them. Let us thus be warned of unbelief, for from unbelief springs forth this hostility to God and all lawlessness. Joshua and Caleb were not more righteous than all their brothers, but they were righteous in that they believed. And thus they entered in to Canaan.

And you will destroy all this people. It is to be noted here that Moses did not say 'God' will destroy them. Unbelievers destroy themselves with their own faithlessness. Remember when Christ said:
Luke 7:50 (ESV)
And he said to the woman, "Your faith has saved you; go in peace."
As the believer saves himself from eternal condemnation by his own faith, likewise the unbeliever condemns himself with his own unbelief. Christ will say to the unbeliever on the last day: "Your unbelief has damned you; go into everlasting death, where you will have no rest". Unbelief destroys oneself. Just as the first generation had no one to blame but themselves for not entering in Canaan. those who go to hell have no one blame but themselves. God has given everything to man that he may save himself and not die. He has given His own Son and killed Him for us, that whosoever believes may live. No man in Hell will blame God for his torments, but will forever blame himself for refusing to believe in such a loving God. Therefore hell will be a place of eternal self-pity and regrets:
Matthew 13:49-50 (ESV)
The angels will come out and separate the evil from the righteous [50] and throw them into the fiery furnace. In that place there will be weeping and gnashing of teeth.
Let us have faith in our hearts, that we may be able to rejoice in heaven for the choice we made while we were in the world to believe in Him. We will say: 'Though the way was painful, following Christ was worth it. Though the world laughed at us, they are weeping now, and now we rejoice. Our labour in faith was not in vain'. Amen.