Question: "What are Pelagianism and Semi-Pelagianism?"
Pelagius was a monk who lived in the late 300s and early 400s A.D. Pelagius taught that human beings were born innocent, without the stain of original or inherited sin. He believed that God created every human soul directly and therefore every human soul was originally free from sin. Pelagius believed that Adam's sin did not affect future generations of humanity. This view became known as Pelagianism.
Pelagianism contradicts many Scriptures and scriptural principles. First, the Bible tells us that we are sinful from the moment of conception (Psalm 51:5). Further, the Bible teaches that all human beings die as a result of sin (Ezekiel 18:20; Romans 6:23). While Pelagianism says that human beings are not born with a natural inclination towards sin, the Bible says the opposite (Romans 3:10-18). Romans 5:12 clearly states that Adam's sin is the reason sin infects the rest of humanity. Anyone who has raised children can attest to the fact that infants must be taught to behave; they do not have to be taught how to sin. Pelagianism, therefore, is clearly unscriptural and should be rejected.
Semi-Pelagianism essentially teaches that humanity is tainted by sin, but not to the extent that we cannot cooperate with God's grace on our own. Semi-Pelagianism is, in essence, partial depravity as opposed to total depravity. The same Scripture passages that refute Pelagianism will also refute Semi-Pelagianism. Romans 3:10-18 definitely does not describe humanity as only being partially tainted by sin. The Bible clearly teaches that without God drawing us, we are incapable of cooperating with God's grace. No one can come to me unless the Father who sent me draws him (John 6:44). Like Pelagianism, Semi-Pelagianism is unbiblical and should be rejected.