I have appreciated much of Pastor Chuck's ministry. On this issue, however, I think he made serious errors. Pastor Chuck did not sufficiently recognize the difference between the outward, visible church (everybody who shows up on Sunday) and those who are in fact regenerated by the Holy Spirit (the smaller number of true believers). Struggling to make sense of those who depart from professions of faith, he began to think that saved people could become "unsaved" based on their (un)cooperation with the Spirit.
It is worth noting, this was the central point over which Protestants cut ties with the Roman Catholic Church in the 1500s, and Pastor Chuck stood with Rome on this issue. Scripture is emphatic, however, that God will always "finish the work he began in you, to the day of Christ Jesus," (Phil 1:6). Those who "leave the faith," as Pastor Chuck says, prove they were never in fact converted by the Spirit. "They went out from us, but they were not of us; for if they had been of us, they would have continued with us. But they went out, that it might become plain that they all are not of us" (1 Jn 2:19). Those who are born again have received an "incorruptible seed" that cannot die. "For you have been born again, not of perishable seed, but of imperishable, through the living and enduring word of God" (1 Pet 1:23).
This beautiful doctrine that salvation rests entirely upon the work of Christ applied by the Spirit, does not make true believers lazy about sanctification or comfortable with sin. How could it, for the same Spirit who grants new birth also imparts a new and living nature! One that loves holiness and thirsts for righteousness.
Moreover, God the Father "disciplines every son whom he loves" (Heb 12:6). Even when they stray, regenerate souls are brought back. In this sense, the Prodigal Son never "lost" or "left" his salvation. He may have forfeited the comforts of home for a time, but he was always hidden in his Father's heart. According to the election of mercy, it was only a matter of time before he was drawn home by cords of indelible love (2 Thes 2:13).
Do not misunderstand me, I do not question Pastor Chuck's faith in Christ. Yet it is worth warning others that this particular view of his tends to make people think of salvation as being decisively conditioned on something we must contribute to God's grace. It causes people to depend on their own inward resolve, something God cannot or will not give or create for them, instead of depending solely on the Father's grace for their entire future of faith and daily repentance.
In reality, regeneration and sanctification are not unlike the gracious transformation we trust God to complete at glorification. Just as our dying day will bring total freedom from inward corruption and unbelief through a sovereign act of transforming grace, so God is always at work in believers, renewing and freeing them from the old nature. This is not a denial of human responsibility. Rather, it speaks to our beautiful faith in God to free us daily from corruption for Christ's sake, so that we may obey in a spirit of gratitude and sonship.
Verses that warn against falling away, I take as means by which God stirs his children up to ask, "what am I really trusting in, and what evidence do I show of having the Spirit?" In this way, we never stop "making our calling and election sure." Each day we are called to self-consciously "set our hope fully on the grace that will be brought to you in the day of Christ Jesus" (1 Pet 1:10, 13). We continue to "work out our salvation," by constantly reaffirming that "it is God who works in you both to will and to do, according to his good pleasure" (Phil 2:13). It is truly encouraging to find all our hope in the Spirit of mercy, who is "able to keep you from stumbling and to present you blameless before the presence of his glory with great joy" (Jd 1:24).
POSTSCRIPT: When speaking about Christian perseverance, I have found it helpful to avoid framing the discussion in terms of “freedom of the will.” Rather, I focus on God's power to sanctify. Freedom of the will is somewhat of a misnomer, anyway. God cannot will himself to sin—does that mean he doesn't have “free will”? No, it means that his nature is totally free from corruption and the potential to deviate from holiness. We, however, deal with many corruptions and tendencies to doubt. Our fallen human nature inevitably influences our wills toward unbelief and sin. Thankfully, God is in the process of transforming our nature! That is our hope for endurance, not that we have strength from ourselves, but that "he who has called you is faithful, and will also do it" (1 Thes 5:24).