18 having their understanding darkened, being alienated from the life of God, because of the ignorance that is in them, because of the blindness of their heart;
The next two clauses explain why non-Christians are “alienated from the life of God.”
because of the ignorance that is in them,
The reason Gentiles were alienated from God was due to (1) their prevailing “ignorance” and (2) “blindness of their heart.” First, they were ignorant of the fact that there is an alternative life, eternal life.
Gentile ignorance was culpable ignorance; they had no excuse for it. Failure to respond to revelation made their ignorance vulnerable to judgment. Their ignorance was “in them” and was blameworthy.
Ac 17:30, Truly, these times of ignorance God overlooked, but now commands all men everywhere to repent…
because of the blindness [hardness] of their heart;
“Blindness” is literally hardness. Secular Greek used this word for a callus—that is, skin hardened so that it is not sensitive to touch. The idea here is a calloused soul. Their calloused soul had a willful determination to continue in their scheme of negative volition toward God. Greek grammar says that they arrived at this condition of callousness by constantly going negative toward God’s revelation.
Constant rejection of God produces a callousness toward God that makes it very difficult to respond to God.
Non-Christians may be religious and nice, but nevertheless they possess a hard heart toward God. They are spiritually dead to God (Eph 2:1). They are implacable toward God and His Word.
Non-Christian darkening and alienation to God is traced to their culpable ignorance. Negative volition toward God and His revelation produces a calloused attitude toward God. Having decided to go negative toward God at a point in the past, they came to a point where they could not believe (Re 22:11). Satan is behind this hardening of heart (2 Co 4:4).
Pharaoh hardened his heart against God (Ex 4:21). He developed this hardness by constantly going negative to God. In the same way God allows those with entrenched negative volition to sink into degeneracy.
Jn 12:37, But although He had done so many signs before them, they did not believe in Him,
39 Therefore they could not believe, because Isaiah said again: 40 “He has blinded their eyes and hardened their hearts, Lest they should see with their eyes, Lest they should understand with their hearts and turn, So that I should heal them.”
Constant rejection of light eventually produces a greater darkness toward God and greater difficulty to respond to God.