I'm sorry. I went back to the post where I thought you said it and I see, based on the rest of our discussion, that you were probably addressing the first part of my post concerning the Ephesians passage, not the second part about the Hebrews.
We're good.
All called people are illuminated by the testimony of the Holy Spirit (the testimony of the Spirit about Jesus IS the illumination). Some of the called choose to retain the testimony of the Holy Spirit about Jesus in their heart and are saved and receive the promise of eternal life. Others choose not to retain the testimony of the Holy Spirit about Jesus in their heart and do not receive the promise.
1 John 5:6-12 NIV
"It is the Spirit who testifies, because the Spirit is the truth. 7For there are three that testify: 8the Spirit and the water and the blood; and the three are in agreement. 9If we receive the testimony of men, the testimony of God is greater; for the testimony of God is this, that He has testified concerning His Son. 10The one who believes in the Son of God has the testimony in himself; the one who does not believe God has made Him a liar, because he has not believed in the testimony that God has given concerning His Son. 11And the testimony is this, that God has given us eternal life, and this life is in His Son. 12He who has the Son has the life; he who does not have the Son of God does not have the life."
Now Hebrews 6:4 itself does not specify if the illuminated Hebrews he is talking to are the illuminated people who retain the testimony of God in their heart and are saved, or whether they are the illuminated people who have not retained the testimony of God. That information comes from other passages in Hebrews.
I agree that those who don't have the specific message from the scriptures about the Messiah and obedience to God (see Romans 2:12) have far less of a revelation of God than those who do. But among those who do have the scriptures and to whom the Holy Spirit has testified about the Son they are illuminated equally (within the scope of the talent given, of course). But only some of these people educated and illuminated by the Holy Spirit about the Son in scripture retain what they have received and are saved. The rest cast the revelation of the gospel behind them and are lost.
So it's not a matter of being 'illuminated vs. not-illuminated, or not so illuminated'. It's about what people do with the illumination of the Holy Spirit they have received.