I have a question that most Bible teachers stay away from. Here it is: is it possible for a person to harden his heart to where he is beyond salvation?
I believe after repeated denials and refusals where salvation is concerned, people can become polarized to the point where their minds are beyond changing. For example, Paul said that after the rapture many people who have rejected the truth will believe the lie. Seeing that their minds are made up God will actually influence them to accept the lie that the anti-Christ is God. (2 Thes. 2:9-11)