Josh 1:7 "Only be strong and very courageous, that you may observe to do according to all the law which Moses My servant commanded you; do not turn from it to the right hand or to the left, that you may prosper wherever you go."
All those entering the Promised land were strong and courageous to keep His laws and prosper in all their endeavours. But those who had witnessed the 10 plagues against the Egyptians, the opening of the Red Sea, and many other miracles were faithless. When told that the Canaanites were powerful with high walls and there were also giants there, they rebelled against God (Moses) when faced with certain defeat and death.
Num 14:3-4 "Why has the Lord brought us to this land to fall by the sword, that our wives and children should become victims? Would it not be better for us to return to Egypt?" So they said to one another, "Let us select a leader and return to Egypt."
Mat 24:4-5 And Jesus answered and said to them: "Take heed that no one deceives you. For many will come in My name, saying, 'I am the Christ,' and will deceive many.
Today Christians (just like the Israelites) are glorifying the Lord for the numerous miracles they saw (TV), heard (testimonies), read (books) and their wonderful encounters with God. But without truth and understanding of the gospel many of these Christians, when told by our Lord to suffer and possibly lay down their lives for the furtherance of His kingdom, will rebel against His words. Out of fear of sacrifices, sufferings and possibly death, these will deceive themselves with heresies such as prosperity gospel, positive confession, hyper-faith, etc.
Deut 11:18-19 "Therefore you lay up these words of mine in your heart and in your soul, and bind them as a sign on your hand, and they shall be as frontlets between your eyes. You shall teach them to your children, speaking of them when you sit in your house, when you walk by the way, when you lie down, and when you rise up."
Those born and raised up in the wilderness were taught the words of God and most of them memorized the Torah. These spiritual Israelites were fearless entering the Promised land.
Rev 4:6-8 Then I saw another angel flying in the midst of heaven, having the everlasting gospel to preach to those who dwell on the earth - to every nation, tribe, tongue, and people will- saying with a loud voice, "Fear God and give glory to Him, for the hour of His judgment has come; and worship Him who made heaven and earth, the sea and springs of water." And another angel followed, saying, "Babylon is fallen, is fallen, that great city, because she has made all nations drink of the wine of the wrath of her fornication."
During WW3 (fall of Babylon - the West), the everlasting gospel will be preached to the new converts (the angels will kill all those preaching lies, another gospel and heresies), which includes the message of the cross, resurrection, and end time events.
Once these new converts believe and keep His words, our Lord Jesus will baptize them in the Holy Spirit. The Spirit of Truth will then teach and guide them into all truth so that just like the spiritual Israelites, they will be strong and courageous to face the persecutions and martyrdom, knowing that the Spirit of God will be with them to lead, guide and protect them.
John 16:13 "However, when He, the Spirit of truth, has come, He will guide you into all truth; for He will not speak on His own authority, but whatever He hears He will speak; and He will tell you things to come."