The ‘T’ in TULIP, sometimes called Total Inability or Radical Corruption, is probably the 2nd least favorite of the five points of Calvinism not far behind Limited Atonement. Now there have been tons of books, and articles done that are going to provide you a better understanding, but I needed a reason to post today so I appreciate you taking the time to read my version.
“But of the tree of knowledge of good and evil, thou shalt not eat of it; for in the day that thou eatest therof thou shalt surely die.” – Genesis 2:17
The idea of Total Depravity, as understood by most of Reformed Christianity, is this; Mankind has been made, through the disobedience of Adam, wholly and totally spiritually corrupted so much so that from birth they are led by a sinful and ungodly nature and are unable to do anything spiritual or acceptable to God. This nature is sometimes referred to in the Bible as the natural man.
What does this mean exactly? The Scriptures declare that mankind is a willing slave to sin, and entirely unable to free himself from slavery. In the first epistle to the Corinthians chapter 2, Paul says that “the natural man does not receive the things of the Spirit of God: for they are foolishness unto him; and he cannot know them , because they are spiritually judged.” (1 Cor 2:14) In Paul’s letter to the Romans chapter 3, he says “no one understands; no one seeks after God”. (Rom 3:11) In John 3, Jesus says that “unless a man has been reborn in Spirit, he cannot see the kingdom of God.” (John 3:3/5)
So the Bible tells us that mankind, in their fallen condition, is unable to do anything that is pleasing to God or to move toward Him. Yet, this does not mean that mankind is as evil or as corrupt as they possible could be. God restrains sin so that mankind is not entirely destitute of any virtue. In other words, though the natural man is actuated or moved by wrong principles, and therefore incapable of doing anything that would merit righteousness before God, he can still do ‘good’ or ‘noble’ deeds for fellow man.
If man is a slave to sin, unable to free himself or do anything to bring himself to God, how are we to be free followers of Christ? Even Job said “Who can bring a clean thing out of an unclean?” (Job 14:14) A clue can be found in Ephesians 2 “But God being rich in mercy, because of the great love with which he loved us, even when we were dead in our trespasses, made us alive together with Christ by grace” (Eph. 2:4-5) and Titus 3 “He saved us, not because of works done by us in righteousness, but according to His own mercy, by the washing of regeneration and renewal of the Holy Spirit” (Titus 3:5).
So if we consider these in light of what Jesus said in John 3, we should have the answer of how the spiritually dead are freed from captivity. Allow me to quote from the Westminster Confession, which says it better than I – “He is pleased, in His appointed and accepted time, effectually to call, by His Word and Spirit, out of that state of death, in which they are by nature, to grace and salvation by Jesus Christ; enlightening their minds spiritually and savingly, to understand the things of God;”
Now many will argue that man has a will, a free will, in order that he might choose to be a follower of Christ and that once they believe they are then changed. The problem with this is that our free will is limited and not autonomous. We must follow that which rules us, and in the case of the unbeliever it is his sinful nature. In Jeremiah 13, the prophet offers a rhetorical question “Can the Ethiopian change his skin or the leopard his spots?”, the answer of course being no, and he goes on to say “Then also you can do good who are accustomed to do evil”. (Jer. 13:23) In other words, the fallen man is unable to do that which is different from his nature.
This is the essence of the Old Testament, the bad news in which the good news of the gospel shines brightest. Mankind cannot do it, he cannot save nor can he keep himself because he will always fail to do what is right. It has to be entirely of God. The spiritually dead are paralyzed, completely incapable of bringing himself right with God. God must administer the cure directly, into the heart. But He does not only change a man but He also secures him, so that whomsoever the Father gives to the Son, they shall not fall away.