He doesn't grasp it because it is non-sense, if you will pardon the expression.
You can not have a person responsible who is not also able or have the ability to do the very thing you have made them responsible for.
By the same token, one is not culpable unless they have the ability to do or act accordingly.
By the very laws of justice that God set forth, it is unjust.
Ergo, God would not do so either, being that He is a Just and Righeous God.
The expression above is the clearest I've seen on this board of a TOTAL misunderstanding of the gospel. WE CANNOT do a single thing in and of ourselves to make amends with God. It is IMPOSSIBLE. We are DOOMED.
That is precisely why the gospel is the "good news." Jesus Christ came to do what was/is/and ever shall be impossible for humankind, i.e., to do a single thing to extract ourselves from our doomed and damned state.
We are indeed culpable for our sin, for as the Bible says SO clearly, "All have sinned and fall short of the glory of God." But, we have NO ability whatsoever within us to remedy that culpability, save that God so loved the world that He sent His only Son to redeem those who are lost without hope.
ANY other expression is not of God, for it could potentially eliminate the need for God, as a righteous man might potentially be able to live in such a manner as to satisfy God's requirements and no man has, or can, or will, save the ONE perfect man, Christ Jesus who came to give the rest of us life.
The whole of the Bible is given over to this basic doctrine. "There are none righteous, not one..." "All your righteousnesses are as filthy rags..." "They are all gone astray, all together are filthy, there are none who do good, no not one..." "You are dead in your sins..." "We cannot stand before You because of our trespasses..."
Paul wrote this:
2Cr 5:19 To wit, that God was in Christ, reconciling the world unto himself, not imputing their trespasses unto them; and hath committed unto us the word of reconciliation.
And this:
Col 2:13 And you, being dead in your sins and the uncircumcision of your flesh, hath he quickened together with him, having forgiven you all trespasses;
The fundamental and fatal flaw in doctrine and belief that WE somehow can come to Christ based on something within us is alien to the Scriptures. It is God who comes to us, always and only, and praise Him, effectually to those whom He elects.
All else is a false gospel and a false doctrine based on a false reading of Scripture.