Who you speak about are the 'lukewarm' Christians, who are on the cusp of 'falling away'. Their faith is at a point where Satan is working full-force to prevent their salvation, as is his plan for the whole world. If they are not grounded, their root of faith, deep into the 'good soil', then they are ripe for his attacks and we are told that a good majority of Christians will fall away. Some will say they are not true Christians, but I believe they are; they are in the very first stages and do indeed believe, but because their walk is just beginning they will fail our Lord and themselves in the end. They are trying to worship both, mammon and God, but it is not possible, all will fall to one side or the other, hence the many warnings for us to protect our faith.
16 Don’t you know that when you offer yourselves to someone to obey him as slaves, you are slaves to the one whom you obey—whether you are slaves to sin, which leads to death, or to obedience, which leads to righteousness?
16 So, because you are lukewarm—neither hot nor cold—I am about to spit you out of my mouth.
1 Timothy 4:1
4 The Spirit clearly says that in later times some will abandon the faith and follow deceiving spirits and things taught by demons.
4 It is impossible for those who have once been enlightened, who have tasted the heavenly gift, who have shared in the Holy Spirit, 5 who have tasted the goodness of the word of God and the powers of the coming age, 6 if they fall away, to be brought back to repentance, because to their loss they are crucifying the Son of God all over again and subjecting him to public disgrace.
7 Land that drinks in the rain often falling on it and that produces a crop useful to those for whom it is farmed receives the blessing of God. 8 But land that produces thorns and thistles is worthless and is in danger of being cursed. In the end it will be burned.
2 Peter 2
2 But there were also false prophets among the people, just as there will be false teachers among you. They will secretly introduce destructive heresies, even denying the sovereign Lord who bought them—bringing swift destruction on themselves. 2 Many will follow their shameful ways and will bring the way of truth into disrepute. 3 In their greed these teachers will exploit you with stories they have made up. Their condemnation has long been hanging over them, and their destruction has not been sleeping.
4 For if God did not spare angels when they sinned, but sent them to hell, putting them into gloomy dungeons to be held for judgment; 5 if he did not spare the ancient world when he brought the flood on its ungodly people, but protected Noah, a preacher of righteousness, and seven others; 6 if he condemned the cities of Sodom and Gomorrah by burning them to ashes, and made them an example of what is going to happen to the ungodly; 7 and if he rescued Lot, a righteous man, who was distressed by the filthy lives of lawless men 8 (for that righteous man, living among them day after day, was tormented in his righteous soul by the lawless deeds he saw and heard)— 9 if this is so, then the Lord knows how to rescue godly men from trials and to hold the unrighteous for the day of judgment, while continuing their punishment. 10 This is especially true of those who follow the corrupt desire of the sinful nature and despise authority.
Bold and arrogant, these men are not afraid to slander celestial beings; 11 yet even angels, although they are stronger and more powerful, do not bring slanderous accusations against such beings in the presence of the Lord. 12 But these men blaspheme in matters they do not understand. They are like brute beasts, creatures of instinct, born only to be caught and destroyed, and like beasts they too will perish.
13 They will be paid back with harm for the harm they have done. Their idea of pleasure is to carouse in broad daylight. They are blots and blemishes, reveling in their pleasures while they feast with you. 14 With eyes full of adultery, they never stop sinning; they seduce the unstable; they are experts in greed—an accursed brood! 15 They have left the straight way and wandered off to follow the way of Balaam son of Beor, who loved the wages of wickedness. 16 But he was rebuked for his wrongdoing by a donkey—a beast without speech—who spoke with a man’s voice and restrained the prophet’s madness.
17 These men are springs without water and mists driven by a storm. Blackest darkness is reserved for them. 18 For they mouth empty, boastful words and, by appealing to the lustful desires of sinful human nature, they entice people who are just escaping from those who live in error. 19 They promise them freedom, while they themselves are slaves of depravity—for a man is a slave to whatever has mastered him. 20 If they have escaped the corruption of the world by knowing our Lord and Savior Jesus Christ and are again entangled in it and overcome, they are worse off at the end than they were at the beginning. 21 It would have been better for them not to have known the way of righteousness, than to have known it and then to turn their backs on the sacred command that was passed on to them. 22 Of them the proverbs are true: “A dog returns to its vomit,” and, “A sow that is washed goes back to her wallowing in the mud.”